I want a new person to make Smash, and a fresh reboot to start off. A high 20-low 30 roster will do, and add clones to pad it out for a decent number. Subsequent games can tweak the clones as seen fit. Sakurai can work the negotiations for whatever hype shill rep Nintendo wants to push, but he cannot have a say in anything else.
Yes, I know Nintendo would be more hands-on with the new guy if not outright making the choices for the roster but Sakurai's had too much time with the franchise and his stuff has been stagnant since Brawl.