Give returning characters new moves, no clones or echos, new stages, new single player modes, more new comers ect.
Outside of the clones part (which I mean, wouldn't drastically save them much dev time) this describes every game in the series. You're describing a sequel with cuts. The fact that you described them as returning characters in the first place means we're not that serious about renovating the roster.
Because in a roster of say, 30 characters, how many of them would reasonably not already be on the roster? Even if we started entirely from scratch? Smash's structure lies on a sort of inarguable hierarchy. You need Mario, Donkey Kong, Link, Samus, Kirby, Pikachu, Inkling. One or both of Villager and Isabelle. Someone from Fire Emblem, someone from Xenoblade, someone from Pikmin. Luigi, Peach, Bowser, Zelda, Ganon/Dorf. Yoshi and Wario. Fox, Ness and Captain Falcon are not going anywhere regardless of what anyone says and Mii Fighter costumes are pretty much a permanent fixture of Smash's economy. That's already 22 characters who NEED to be here - that is literally the barest possible minimum, and I probably even forgot a couple.
So then who are the newcomers who justify cutting King Dedede, Diddy Kong or Ridley? Does the inevitable new Pokemon really warrant cutting Charizard and Lucario? In this way Smash has kind of shot itself in the foot, but it was bound to happen. The game is built around introducing everyone's favorite characters, and at some point or another we establish characters who cannot be directly replaced. A complete overhaul removing the bulk of the roster and adding some fresh new faces sounds good on paper, but starts to feel a little ridiculous when you're subbing in I dunno, Raven Beak over Ridley or give Dixie Kong a go without Diddy. That just is not how this series operates and would do more to alienate millions of fans than anything. Subbing in less popular characters at the expense of more popular characters is kind of just a bad idea. So many of these series end up at a standstill.
And as I addressed yesterday, a lot of characters don't need moveset overhauls. Change for change's sake accomplishes pretty much nothing. We can stand to bring Samus up to speed with the current state of Metroid, give Mario some new powerups, maybe give Villager a growth spurt. But this isn't
reboot material. If the team wants to switch up characters they will, any of these pretty much just sound the same as what Link got in Ultimate. Changes more drastic than this would just feel arbitrary, we don't need Mario's entire moveset to change just so we can slap a big NEW on it.
There are two scenarios that I feel would justify a true roster overhaul. One is limiting series to one or two fighters each, focusing more on "representatives" on behalf of their entire cast. I don't think this would be very satisfying, but it's something. Maybe it gives them an excuse to explore lesser known series and those that have missed the boat like Golden Sun, Rhythm Heaven , Sin & Punishment. The other angle is a roster focused much more heavily on third party dynamics and becoming more of a "Nintendo Vs" styled game. Personally I'd love to see something like this, but maybe independent of Smash. That feels more like a side mission than a change of direction entirely.
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