So, I'm sure that this idea has been juggled around before, but what if SSB4 was on the 3DS, and featured mostly Handheld-only characters, like Isaac and Professor Layton, and it was followed by a SSB4 on the next home console, featuring mostly console-exclusive characters, like Mii and Little Mac?
I've already got a roster idea, but it's still a WIP, so judge based on that.
45 characters, no guest characters, limit of 4 characters per franchise(For now...Next Console Smash will probably add more...). 9 rows of 5, and go!
Mario, Luigi, Peach, Bowser, Yoshi(Mario series, Yoshi series)
Donkey Kong, Diddy Kong, Wario, Captain Falcon, Samurai Goroh(Donkey Kong series, Wario series, F-Zero series)
Link, Zelda/Sheik, Ganondorf, Toon Link, Tingle(Legend of Zelda series, Tingle series)
Samus/Zero Suit Samus, Ridley, Fox, Krystal, Wolf(Metroid series, StarFox series)
Kirby, Metaknight, King Dedede, Starfy, Ray MK II(Kirby series, Starfy series, Custom Robo series)
Pikachu, Jigglypuff, Blaziken, Zoroark, Isaac(Pokemon series, Golden Sun series)
Marth, Roy, Eirika, Professor Layton, Andy(Fire Emblem series, Layton series, Advance Wars series)
Ness, Lucas, Masked Man, Villager, Jill(Mother series, Animal Crossing series, Drill Dozer series)
Pit, Mr. Game & Watch, Muddy Mole, Alice, Nester(Kid Icarus series, Game & Watch series, Mole Mania series, Balloon Kid series, Nintendo Power/FUNKEH BOWLING YEEEAH).
However, I'm not really sure about Nester, Andy or Jill Dozer-if anybody's got any ideas for various characters, or for a Game Boy mascot, I can definitely consider them.
Also, I removed some characters because they're not really relevant to handhelds(Ice Climbers, ROB, Olimar, Falco, Ike) or they're not really relevant anymore in general(Pokemon Trainer, Lucario).