That could maybe work, but I think you're confused about some things. Yes, StarFox 64 can be beaten in under 30 minutes (check out speed demos); to FULLY beat the game, it take 1.5 hours. But guess what...so can Metroid Prime and that is a modern game. Fact is, people spend hours and hours and hours mastering a game so that any game is reduced down to a few hours at most.
I do agree that they should take that and make it even better and more challenging, but I don't think that that is a valid argument talking about a game being too easy because someone can beat it in a few hours.
The game offered 3 different paths,and two slightly different endings,but there is no way I would ante up $60 bucks for a game that I could travel all 3 different paths and get the Bad and Good ending in just about 3 hours.
Honestly you would put Starfox 64 on a shelf right now and sell it for 60 bucks?The game is really nice,and I never even had a problem with it being to easy.
But if you were to create a rail shooting Starfox game right now,it would have to be much longer than Starfox 64(Which would create a problem within itself,because exactly how long can you keep a rail shooter interesting,without going too overboard on the length?),or have 9 or 10 different endings like Starfox Command did.
I love the old formula,but it's not as easy as it looks to keep everybody interested.Either you will have new people complaining about only piloting in the ships or you will have older fans complaining about too much time spent outside of the ships.