These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Angst? What Angst?: One of Tobia's defining characteristics. While it's not like he doesn't angst at all (this is a Gundam story after all), he can sleep it off and be completely fine the next day. Played with when he has to act shell-shocked to (briefly) infiltrate the Jupiter Empire.
Arc Fatigue: Volume 5 starts with Mother Vanguard sunk and Kincaid supposedly killed, but then it hits the brakes for a while and focuses on Tobia, Berah, and Bernadette on Earth undergoing a collective Heroic BSOD over said events, sitting out the war as the Jovians walk all over the Federation. It isn't until Kincaid comes back at the start of Volume 6 that things pick up again.
Cargo Ship: Grey Stoke has a brotherly bond with the Gump. Which makes sense, since he's been using it ever since it was called the ZZ Gundam.
Not to mention the fight where he takes on the Death Gale team by himself and wins. Particularly, taking out the heavily armored Tortuga by stabbing a beam saber into its shoulder, then punching it out the other side.
Kincaid isn't to be outdone himself. Gundam establishes that the F91's VSBR weapon is capable of penetrating beam shields. When faced with F91s, what does he do? Layers his shields, along with his beam zanber, allowing him to stop the "unstoppable". And, of course, the fight mentioned under Crippling Over Specialization.
Adding to the awesome of that battle is the Mother Vanguard's Death or Glory Attack, where it charges in full speed ahead with its beam shield active, and then once it penetrates the Jovian line it opens up with a broadside from its port and starboard beam cannons. Unfortunately, Bera was undergoing a minor Heroic BSOD at the moment, so this awesomeness fell to the Mother Vanguard's unnamed helmsman.
In Steel 7, Tobia pulls off an apparently suicidal charge against Callisto's Digitus, using Full Cloth's skull gauntlets as a boxing glove...and then he activates out the brand markers, one of the most often forgotten weapons in the Crossbone's arsenal, which he was hiding underneath the skull gauntlet and lands the killing blow.
Tobia's final battle with Crux Dogatie. Dogatie is in a mech the size of a skyscraper and Tobia is in his Gundam. Tobia WINS by using his mech to kamikaze Dogatie's.
In Ghost you have Font managing to survive and escape from an attack by both Jovians and the Zanscare Empire with a Zaku left over from the One Year War long enough to be rescued by an oddly calm blind man revealed to be an older Tobia Arronax.
Crowning Moment of Funny: In the second chapter, Berah is in the shower when she spots someone outside. Her response is to chase the Peeping Tom out...while instantly assuming it's Kincaid. For extra comedy points, he's nearby when she starts angrily yelling his name, and his reaction has a definite "fear of God" element to it, making it look like Berah has good reason to suspect him.
Just about the entirety of Skull Heart chapter "Satellite of the Apes". Harrison is assigned to investigate an old Zeon research satellite, under advice from an ancient Zeon stalwart (who actually has to physically stop himself from doing the Sieg Zeon salute a couple of times). What's at the satellite? Newtype monkeys, piloting four-armed Zakus, part of a project started by Garma Zabi after witnessing a monkey playing Pac-Man. And the monkeys kick Harrison's ass until Tobia uses the Crossbone's cape, yellow spray paint, and oxygen tanks to make a giant banana-shaped balloon that distracts them long enough for Harrison to shut them down.
Fanon: Fans like to believe that Tomino's original proposal for Gundam F91 included Crossbone; it's uncertain, but seems pretty unlikely.
Genre-Busting: It's almost hilarious just how much better this series is than a lot of other Gundam entries, just because it doesn't subscribe to most of the tropes associated with it. And even if YMMV on the "better" part, that the series is so different is pretty obvious.