Well, Assault is the direct sequel. And then Command, but it had 9 different endings, so I don't count it as Starfox storywise. Command was repetitive, the designs of the characters were horrible (And I'm not sure why they though it was a good idea to mix it with Assault's and take it over to Brawl/Smash4), and the story was 150% failure (Multiple butterfly effects are never gonna fit in the Starfox Universe). And Krystal stayed through all the games outside the port to 3ds and perhaps this one. I imagine that SF:Zero will be after Andross, but before Adventures (Like Starfox 2 was). But all the ideas there had already been done in Starfox 2 and they just now decided to revive them I guess (Which is why I said they'll prob add Fay/Miyu as dlc since nintendo seems to be going that route like all the others).

Well, there's like 6 unused characters in the starfox universe game wise.
Apparently, James (Fox's dad) flew with a mouse and bear before Peppy/Pigma.
Then Starfox 2 offered Fay and Miyu (One being a cocker spaniel and the other a lynx).
Then the comic(Which was cheesy as hell and the design was awful. I mean, it was 1990 and it looked horrible) offered Fara (And a lot of unnamed chars). Also gave the name of Fox's mother in it. But the comic has no canon within the game universe.
Apparently in Japan, Adventures came with a story book involving Katt and Falco and the gang members Falco use to run with. Also introduced a new enemy named General Shears, who was trying to revive Andross.

i just dont get what looks so shitty about the new starfox game to you, is it just the gameplay that bothers you? so far we have no idea of what extent they'll push the story, which seems to be what you want the most out of it.

Well, the design took a step backwards. No where as pleasing as Assault(Hell, looks like they tried to mimic Starfox:64 and failed). I mean, it's 20 flipping 15. They could make it look better.

The story, not the biggest problem really in this game. I assume this is after 64 and they're just cleaning up what's left of Andross' army(Just assumptions. There's prob some one that resurrected him or some hum drum story like that, that has been done already in a comics). It's always about Fox in the end and his father's legacy.
The only thing that bothers me is they didn't complete the story off Command. Because, back then, they said the next game would start DURING the Anglar wars, but without all the retarded endings, like a normal starfox would be(I.e. carrying the story on).

And, well, the vehicles were done in Starfox 2 like I said. So it's nothing new. And adding those clearly ROB things annoy me(I guess because they put him in brawl/Smash 4 as a joke when others chars coulda been used).
Another reason is they're trying to copy Starfox 2, like they did in Command(Not that Command had different vehices, obv, but the free range with multiple choices/endings crap).

Honestly, you would have to be an actually fan (Not a Fanantic that eats all the crap they push out for the series) to understand what I mean when you see previews like that.
Hell, no one on the after show even TOUCHED on it. So, what does that tell ya?