ugh... at least for me starfox adventure was a huge dissapointment. mind you, not only i was very into starfox at the time, and i actually was excited for the game when it still was dinosaur planet on the 64, so when i played the game i reallt wanted to enjoy it. but the game had a trouble development and it shows. at least it run withouth problems and i remember it looked quite pretty. But stuff regarding design didnt left a positive impact on me. and i hated slippy with passion there. whatever i wanted to engage in the game in a more organic way and discover stuff, slippy springed back to say exactly what i needed to do. and you couldnt ignore him.
Regarding Krystal there i may not remember it too well, but didnt she just, did some stuff in the tutorial, only to then be put out of comission in a very convenient glass prision that let us see her ? and that was it...
honestly, if only dinosaur planet happened, i would find tricky a more interesting character anyways.
on the other hand, in command there are plenty of paths and decisions you can take with her, and she displays some sort of agency that builds on her as a character, unlike the other games were she just basically was scenery.
Yeah, if she ever is in, a moveset based on some of the stuff Fox can do on starfox adventures, but as some people said before, EVERYONE have moveset potential, if you put enough work on it. Just moveset potential alone isnt enough (specially if you cant back it up with an unique gameplay theme) Im not against Krystal per se. Starfox certainly benefit stop being a sausage party, but first she needs to establish herself as a character. I liked her in command, but command isnt exactly what people see as the "apex" of Starfox.
EDIT: the quote tool seem to break sometimes :/