Leave Ganon as he is with some changes, like having Warlock Punch / Dead Man's Volley in Ryu-style controls. Honestly, Dead Man's Volley is all I truly think we need to make Ganon "canon". The volley, the choke hold, the pimp slap of flight and a dark energy foot. Ganondorf's already a fun character, and has a lot of good potential gameplay-wise (I don't mean MLG / EVO levels of potential like say Sheik or Pikachu, but then again we have been graced with Dr. Nairo, so...)
That's something I don't think really comes up often. I mean, you make a moveset, sure, but there's no cohesion to it. Characters can have mechanics and such, but what advantages or disadvantages do they give the player? What allows them to make up for any weaknesses? What are the best tactics a player of the character could use? What moves are something completely new and original, something other fighters don't have?
For instance,
. You can give him his KO Punch as "something no other character can do" and that's fine. But how exactly do you convey the feel of their home game, or inspirations for that character, while still keeping it balanced compared to other characters, and making them feel different. So naturally, you make him effin' beast on ground but a really lame stone when in-air. But you can't make it too lame, otherwise he'll fall behind others.
, he's annoying. How do you annoy your opponents? Guns blasting at them from several directions, make them forget that can's there, when their guard's down, rush in and do some fancy grab-aerial combos, oh, you forgot he had a spike? Deal with it. He laughs at your misery, but he's not invincible. Weave through the ducks and the bullets, and hit him straight on. Worst he could do is Allahu Akbar your tush, yet launch himself in the process, leaving him even more vulnerable.
That's my problem with characters like Impa. They have abilities, yes, but I need a cohesive concept that's different. And honestly, that's why I think a lot of characters don't get in or haven't yet. Look at K. Rool's body type, what can he do physically that Bowser doesn't already do? Sure, he's got his weaponry, but what can they do that hasn't been done? Heli-pack's basically DHD / Snake, blunderbuss is Koopa Kids or Mii Brawler, and the crown is Link's boomerang! Show people why they could be different instead of re-hashing concept after concept, that's why characters like nearly all of the newcomers this installment are so refreshing instead of just making every character in design like how fans expect.
/rant