In my opinion, we have enough Pokemon. I hate how there's this obligation to keep adding a new Pokemon for each Smash title. It's unearned representation. So what if there's a frickin' bajillion Pokemon? Character quantity seems like a cheap reason to keep getting reps. If the series was that great - as great as Super Mario or Legend of Zelda - I'd say go ahead, but Pokemon isn't that great - not to me anyways. So I'd rather see other series like Star Fox, Mother or DKC get some more reps. And maybe get some reps for some overlooked games like Sin and Punishment, Custom Robo or Mischief Makers.
EDIT: I'll make an exception for Meowth. He has an actual long-standing iconic status (as opposed to being the flavor of the month), has a distinct and memorable role in the series, and has a cool, memorable personality (as opposed to being merely cool looking). But other than that, I'm good.