Why can you jump so high compared to Real Life and the first game? Simple: Mira has less gravity. And possibly also because everyone is in a super-strong robot body. On that note, during the game's prologue Elma gives the player the choice of either running along the high road or jumping down a cliff and running along the shore. With the latter, she mentions that the player's body was "tough enough" for the leap. Another early sign that everyone had mechanical bodies.
The Japanese name of the Player Character is "Cross" while the English name is "Rook." It's supposed to be short for "Rookie" but consider the directions a rook moves on a chessboard and what shape it makes, and you have a clever tie-in to the Japanese name.
Chapter 10 implicitly raises a curious question: why didn't the Ganglion use the Zu Pharg during the NLA invasion? Chapters 11 and 12 then answer this in subtle ways: the Zu Pharg was most likely built solely to destroy the Lifehold in one fell swoop, and it was never meant for frontline combat (considering that Team Elma takes it out on their own...). Considering how much intel Lao was leaking to the Ganglion, they had to have known about the Lifehold's super-tough Deflector Shields and designed a weapon strong enough to punch through them quickly. This is borne out in the actual cutscenes in Chapter 12 when the Ganglion fleet wastes a lot of time and energy shooting at the shields, and Luxaar has to use the half-destroyed Vita Skell to go into battle as a last resort: neither of these would probably have happened if they had the Zu Pharg. Now it really makes sense why in Chapter 10 Luxaar was so pissed off at Ryyz and Dagahn for stealing the weapon. And in a sense, Ryyz and Dagahn stealing it and getting it destroyed inadvertently saved the Lifehold by forcing the Ganglion to use inferior weapons in the Lifehold siege, giving BLADE enough time to rout their forces.
Why is Elma given such a preferential treatment compared to the other BLADEs (she gets to personally handpick her teammate, got more comfortable living quarters for her team than the rest, can pretty much enter NLA's leaders' office unannounced)? Given that she spent three decades dramatically improving Humanity's technology and made the ECP possible in the first place, the Powers That Be being rather deferential and granting more prerogatives to the person who saved their species actually makes a lot of sense.
Why would the Orphe develop such an odd means of reproduction? Because their homeworld had creatures just as large and dangerous as the ones on Mira. Their survival on such a world required them to develop a means that would ensure the species would continue to live on with even the smallest of numbers.
The Telethia's Adaptational Heroism when compared to the original game may seem strange at first, but then you realize their natures aren't really that much different; the Endbringer is just more benevolent in how it follows it. In both games, they are the guardians of their respective worlds and will eliminate anything they perceive as a disease to that world. In the first game, they were the guardians of the Bionis, Zanza's body, and as far as Zanza is concerned, the perceived disease in question was all other living things on it (which Zanza referred to as "bacteria clinging to my body"). Mira is possibly a sentient planet, but is apparently a lot less malicious than Zanza. The only disease that Telethia, the Endbringer perceives is the Taint and ignores all other lifeforms unless provoked.
While not as young as Lin, one would wonder at first glance how exactly a 19-year old Mia was granted passage on the White Whale. As you do her train of side quests though you learn that not only is she a mechanic, but she specializes in Skell Maintenance. She's able to repair her own on the field and when you consider what Elma told you earlier about how valuable Skells are due to them being in limited supply, it's no wonder why Mia was chosen.
A mixture of both brilliance and horror, you learn from Lao that a large number of people who boarded the White Whale were through their connections, not necessarily because they had the skills for the Future of Humanity. That may explain why there is such a large number of criminals you encounter within BLADE. And as to the reason why that was the case, much like what's said in 2012, construction of the evacuation ships required considerable finding from to private sector. It's unpleasant, but "selling tickets" might be the only reason the ships were finished at all.
Irina's defense may very well be the lowest of any recruitable character in the game. Chapter 11 explains that she greatly misses her brother, and lost much of her will to survive.
Hope is one of the few people The Murderess gets along with. The Murderess is hell-bent on her dream of hoarding money while Hope only accepts as much money to cover her expenses, so the friendship may be more pragmatic than by mercy.
The abilities for the starting weapons are heavy on support (Last Stand and Repair are two examples). This easily fits Rook into the Support/Damage/Tank trinity with Elma and Lin.
Bozé getting along with L and Celica may seem like a case of Story and Gameplay Segregation, unless one looks deeper into his xenophobia. L, being a native of Mira, had his wares and lifestyle ruined by the Ganglion, while Celica was a firsthand victim of the Ganglion's atrocities. Since neither of these characters had any chance of colluding with the Ganglion (the Ma-non were hunted by the Ganglion to be assimilated, and Bozé didn't really care much for the divide between Tree and Cavern Prone), Bozé probably didn't mind working with them. His xenophobia may have been more selective than one may think. Supporting this is post-battle dialogue between Bozé and Celica, where the former invites the latter to meditate with him at some point.
In one conversation Lin says that she sees a male Cross as a father, but a female one only as a big sister. Why is that? Because she already has a mother figure: Elma.
Celica is a Psycorrupter+ who uses Dual Guns instead of Rayguns. Celica is also a rather small girl who is one of the few party members who is not using a Mimeosome. Whatever weapons she uses, she has to be able to carry and use them with her own flesh-and-blood body. It makes sense for her to use light weapons like knives and Dual Guns instead of trying to lug around a Raygun that's as big as she is.
One side quest features a Definian trying to impersonate Mia, and doing a very poor job of it. Mia's analysis of the Definians states that their behavior when in disguise is based on typical psychological profiles. Of course they're going to have trouble doing a convincing imitation of somebody as weird as Mia!
The Ganglion High Command members having drastically different appearances and natural abilities (such as Goetia's bio-electric energy) despite the suggestion of them being the same species makes sense when you realize they are a bio-engineered species. Along with whatever the Samaarians used to make the Ganglion lethally allergic to them, they may have used DNA from other species to create individuals with specific purposes in mind.
It just hit me that Elma is the titular Xenoblade. In addition to the obvious — that she's a Xeno who's a leader in B.L.A.D.E. — she is, effectively a mysterious power from the stars that spurred the "creation" of what is essentially a new world for humanity. And she even wears red.
Early in the game, when the humans are revealed to be remote controlled mimeosomes and their real bodies are in stasis in the Lifecore, we are told that if our mimeosome is destroyed, we are effectively dead until the Lifecore is retrieved and our original body is recovered, so we should treat these imitation bodies as if they were our own. The ending reveals that the central computer of the Lifecore was destroyed on impact, and the mimeosomes were running autonomously the whole time, apparently due to Mira's strange phenomena. Even if the human's DNA survived in the Lifecore's DNA database, any mimeosome that was destroyed, means that person is dead, and there were a lot of mimeosomes destroyed or almost destroyed (including the player) throughout the game.
This is lessened by the fact that nothing outright states those who had their mimeosomes destroyed can't be restored, as whatever power on Mira that's somehow keeping everyone alive may have also saved all the system's data from being erased. It does however emphasis how serious things would have been if the Lifecore had actually been destroyed.
Speaking of the lifehold being destroyed, what if it actually being destroyed actually did cause all the Mimeosomes to shut down? Mira might only be keeping everyone alive through it and the systems being intact despite the damage they've sustained. Luxaar was probably very close to destroying Humanity when the Vita got through the Trion barrier.
Even if it didn't, Elma's real body was inside the Lifehold and controlling her mim from it. Imagine if her mim was the only one to shut down... not only is the individual who saved Humanity gone, but being the only mim to shut down would cause a panic or lead to people wondering if their leaders were hiding something.
Both the ending of the game and Yelv's Affinity Missions leaves some heavy implications for the state of the Player Character. It's revealed that human bodies are no longer living and the Lifehold was destroyed, so by all rights the Player Character should not be living or having a consciousness at all. Yelv's final affinity mission ends with the implication that he was never an actual person, but an android designed to carry out Reclaimer missions. When you put this into perspective, this may be the same exact fate of the Player Character, it would explain why Nagi will not allow you to refuse to join BLADE, why someone as abrasive as Yelv latches onto them so quickly, or why Eleanora refers to you as a good partner for Yelv.
Completing a sidequest chain for Yardley will reveal the secret he's hiding: a machine that allows Mimeosomes to be altered at will, and anything can be changed, including gender. This has horrifying prospects if it fell into the wrong hands: imagine less-scrupulous humans being able to completely alter their identity, literally becoming a new person, whenever they wanted. Criminals could get off scot-free for their crimes, avoid detection, or impersonate anyone. The Delfians' shape-shifting already wreaks havok on NLA, imagine if humans could do this too. You actually get the option to bring this up in-game, but all Yardley does is offer a Hand Wave as to why only Rook can use it. He says it's far beyond the price range or criminals, but is he telling the truth?
A combination of both Brilliance and Horror: where are all the kids?! There are no young kids in NLA, and it's only been two years since Earth was destroyed. You'd think that of the people on the White Whale, some of them would have been children. Well, here's the Awful Truth: like you learn from Hope, kids are liabilities. Both the White Whale and NLA are run under the impression that as long as humanity is in such dire straits, every person needs to contribute as much as possible to the cause. That means children, the physically and mentally infirm, and the very old were not brought along. Exceptions like Lin were only allowed because they were useful, and physical disabilities would be a non-issue since all the humans in NLA are remote-controlled android avatars, and there's a 78 year old man that was simply given a younger-looking mimeosome. That being said, if kids were brought, they were almost certainly stored with the bulk of the passengers in the database...and they are thus almost certainly dead since that database was destroyed.
One basic mission from the Mediators asks the player to collect Crush Rings, which are alien torture devices according to the Collectopedia. The mission description is very... secretive about what they'll be used for, so it's easy to assume the worst.
What if Elma decided to forgo mercy towards Ryyz and Daghan after seeing Goetia's hopeless example? The Ganglion would have had the Zu Pharg ready to crush the Lifehold Core in no time at all. So she did the right thing in the end.
Lao surviving his apparent death in spite of the Lifehold mainframe being destroyed. Considering his Death Seeker tendencies stemming from being cheated out of his family boarding the White Whale, and even with his HeelFace Turn, he's probably not going to very grateful about being resurrected. Worse, if he finds out that the mainframe has been destroyed since the crash-landing and he got brought back while everyone else gets to die for real once their mimeosomes are destroyed, he's probably going to think that some greater power (whether it be the Black Knight, Mira or something else) is out to torment him.