Not to mention how absurd it would be for Paper Mario to throw a
fireball. You know what fire does to paper, right?
Not to mention his model is quite different than normal Mario. Clones generally have similar models, so it would probably be more work making him a clone than to make him unique...
His model is exactly why he shouldn't be in this game,it just won't work.People(people who prefer the "classic Mario") hate on Waluigi because he's not in the main series Marios.In fact they don't want him in the main series because he's a "spin off only" character.Yet they still prefer him over Blue Toad.Now putting him in SSB.4 would make him popular enough to be in a main series Mario and maybe we'll get Waluigi World for Wii U and it'll be a massive hit just like E.T the video game.You see?
I was waiting for someone to point that out...