Pacman's FS would be AMAZING.
lol, I can totally picture for his Final Smash, him eating a Power Pellet, then all your opponents start flashing between their normal colors, solid blue, and solid white. And when they are solid blue or white, they have that "scared ghost"face on! x_x
Other characters that would've been nice to play:
Midna - her FS being she turns into that giant spider-form and jams the giant polearm into the ground creating a huge explosion.
Koopa Kids - each alternate color could be a different Koopaling.
Mouser - always one of my favorite bosses. Wish he would come back in some form.
Miyamoto - one of his smash attacks is he can hit you with a banjo.
or, how about this...?
For his different palettes, the colors of his Letterman jacket would change. Maybe to represent a different console – gray jacket/black trim with red “N” (for NES), cream with red “N” (Famicom), light gray with purple “N” (SNES), black jacket with green and red “N” (N64), faded blue with faded purple “N” (GCN), white jacket with bright blue “N” (Wii). I think it’s also be neat to make his jeans color to represent the fashion of the time the console came out.
And while I'm day-dreaming...
Duke Nukem ("Come get some!"