Hmm, I see where you're coming from, especially when it comes to the number of abilities. But lately I've been playing Return to Dreamland and while I enjoy it, I'm seeing the cracks in the "Super Star fighting game inputs" version of copy abilities. At their worst, they're just a distraction and the variety they provide is empty. I try to use a range of moves, but nothing in the actual level design pushes me to do so outside of the copy ability challenge rooms.
By stripping down the copy abilities almost back to Adventure levels, FL allows for much more focus on puzzle solving. That's why Mouthful Mode fits in so well, because they're basically copy abilities but only available within a limited puzzle/platforming space.
Also, Kirby combat (outside of bosses) has never been all that interesting so nothing is lost without 12 different similar sword moves, 10 of which you won't use anyway. And with bosses, the simplified copy abilities are also a boon. Kirby bosses can get chaotic with the spamming of all the different moves, but simplified abilities and the excellent (if easy) dodge mechanic puts the focus back on learning from and responding to the bosses's moves.
Super Star is still one of my favorite games, but I would honestly be fine if the next 3D Kirby kept the simplified abilities and just added some more, along with whatever Mouthful-esque gimmick they come up with.
