Id have to agree with the sentiment that the newcomers so far are a lot more varied and unique. Sakurai really let it loose and came up with a lot of crazy additions. I feel this roster doesn't pack quite the same punch as Melee and Brawl additions but how they actual play more than makes up for it.
In terms of just the characters themselves, I also think I preferred Brawl's overall cast of newcomers. For this game there are a lot of faces I'm really happy to see show up, but its biggest strength is that every character looks really unique in this game.
The only character that I'm expressing apathy towards is the Mii Fighters. That's mostly because of them being banned online, and the fact that the big hook for them is custom movesets which I don't see myself dabbling in too much.