Cliché Storm: Virtually every character are not-so-subtle expies of various well-known archetypes that has been appearing in war movies, shounen series, and JRPGs; the combination of war story and academic settings make this mostly-seamless. Even their Character Development can be seen coming from a mile away! Luke, I Am Your Father.
Complete Monster: Baldren Gassenarl is the scion of the Gassenarl family, a noble house which is using the dissent and Fantastic Racism among Gallia's nobility to dethrone Archduchess Cordelia and take Gallia's throne for themselves. Already at the start of the game, Baldren and his bunch of terrorists are seen happily slaughtering their way through defenseless Darcsen villages in the name of "racial purity." When their revolution actually succeeds and Baldren, upon discovering that his father Gilbert didn't really believe all the racial superiority crap he was spouting, and was just using it as a front for his own power trip, kills him in cold blood and takes the power for himself, starting even more ruthless anti-Darcsen campaigns. At the end of the October mission, Baldren orders a group of Darcsen workers and civilians to be Buried Alive in the ragnite mines along with Squad G, leaving them to die a horrible death if not for Cosette and her Epiphany Therapy.
V2s. They are introduced in the very first Escort Mission of the game, just to make sure the player feels threatened by their presence. Even after destroying their Supply Vehicle, their damaging interception fire makes it a chore even getting close to or past them. With late-game equipment, however, the V2s become much less of a threat, as they can be picked off from a distance after their shields are down.
That said, they may ratchet back up there if the area's Supply Vehicle is in an awkward situation. There are times where you'll have to run a Lancer between multiple V2s just to get a clear shot at the vehicle.
Come post-game, V2's are promptly overshadowed by Ghost Tanks. They have ludicrously high HP and defense that lets them shrug off even a Lancer Elite or Mauler attack from the rear, and they wield enhanced versions of the V2's laser. In the very last non-DLC map of the game, your units start with THREE of them in your face right from the start, each of them having over 5000 HP! Have fun with that.
Even Better Sequel: Despite downgrading from the PS3 to the PSP, the game manages to stand as a bona-fide sequel in its own right by improving on the already robust battle system of the first game by balancing classes and adding a great deal more customization in the form of advanced classes. Additionally, supporting characters are given far greater character development through character specific cutscenes and missions.
Sadly despite these improvements, various factors have seemingly doomed it, such as being on an unpopular system (at the time) and the cast being considered more generic than the first game's, especially Avan.
Fridge Brilliance: The real reason people are assigned to Class G is unclear results on the aptitude test, which makes it difficult to give them an Artificial Valkyria-amplified role. This explains why every single member of Class G can change classes.
Lavinia once she gets her "Tank Master" Potential (a boost to all stats at practically all times), as that combined with her other potentials can make her nearly unstoppable. As she's the tank commander, combine with the above example for even more mayhem. Not quite as bad as the previous examples, though, since it's only available in post-game content.
Flamethrower APCs. It doesn't have any anti-tank capability, and it dies to a single mine, but it can single-handedly torch, melt, slag, and immolate anything that's not a tank. Those, you can leave to the Lancer you stored inside, and if you come across a mine, well, you have an Armored Tech in there, right? Or if you don't need to worry about mines, there's space for a unit class of your choice. Plop a Fencer in there, and you've basically tripled their first turn movement. They'll even take out bunkers, turrets, and cannon towers in a single blow without having to worry about silly things like facing the back of them.
Goddamn Bats: Despite being one of the most fragile classes, enemy Engineer Elites have the highest evasion rating short of Aces, can inflict status ailments with shocking ease, and can, of course, heal themselves and others.
Replacement Scrappy: Avan, as the main character instead of Welkin, for being an annoying Idiot Hero. One incident fans like to refer to is when he tried to help Cosette get over her hemophobia by shooting himself, then ordering her to treat him. This causes many to overlook his redeeming traits, like his determination and lack of prejudices.
This is the reason why Shuntaro Tanaka, the game's most senior producer, didn't want to add the scene in the game since Avan shooting himself may result in a gunshot wound that can be fatal. Unfortunately for him, the production team opposed him and insisted on adding it, saying that Avan's the kind of guy to do it. Tanaka had no choice but to accept it.
Scrappy Mechanic: The Credit system for changing classes. The amount of credits awarded to each unit are entirely random, and it seems to have just been added to the game for the sake of grinding. Especially noticeable are the Certificates and Diplomas: you can potentially use one unit to do most of the work during a mission, and yet have a character who has done almost nothing get not one, but three of them for a single action.
There is a method of controlling who gets the Lead/Runner Up (e.g. capturing bases is almost twice the credit bonus as killing an enemy soldier) but that just makes it more annoying when the Lead gets Credits they don't need, rather than the ones they could really use right now.
That One Boss: Baldren Gassenarl, especially in the level you first fight him. He has 800 AP (almost twice that of a Scout), a shield that can stop most interception fire, a maul that can One-Hit Kill all but Fencers, and a machine gun like that of a Gunner's for long range and interception. As if that wasn't bad enough, he has the ability to dodge even rear attacks and can use Orders to revive his downed troops every turn and/or teleport from base to base without using CP. He's basically four classes mixed into one (Scout Elite, Heavy Gunner, Medic, and Mauler).
It gets worse. During the rematch (where you have to actually take him out), you find he's swapped out that shield for a breastplate. That's not for show. It basically forces you to get headshots, anti-tank, or area of effect weapons (flamethrowers/swords), and he's still got that interception machine gun.
Some Anvils Need to Be Dropped: The databook of the game says that the inclusion of Artificial Valkyria technology as a major antagonist is a reminder that in the game, it's treated as an easily accessible weapon of mass destruction since in real life, terrorists can get easy access to NBC weapons and use them as weapons.