+ More interesting characters
The inclusion of characters like Olimar, Snake, and Pokemon Trainer, since they don't really do all of their fighting directly, definitely makes for something different from what we had in Melee.
+ Soundtrack
280+ tracks, and a lot of it is good, at the very least.
+ Bigger, more involved single-player
It may not be the incredibly epic story that some people were hoping for, but I'm glad there's an actual plot now, and that you can't just sit down and go through the Adventure mode like you could before.
+ Stage Builder
Anyone that complains that the stages aren't good enough, time to make your own. Granted, you can't do anything as creative as WarioWare or Pictochat, but actually being able to create stages now is nice.
-/+ ROB's inclusion
A lot of you don't like him. I was like that, thinking "Why did they put ROB on the roster? He's gonna suck...", but then I actually saw him in action, and now I feel differently about him.
-/+ 35 characters
While I wanted to see a bigger roster than that (around 40-45), 35 is nice too.
- Cloned Final Smashes
Was it too much to ask to have some sort of difference other than "oh this Landmaster isn't there as long but it's more powerful"? I mean, Wolf could have summoned the Wolfens to fire on the stage for a bit, a la the second part of the Corneria stage in Melee's Adventure mode, but more powerful and focused.
- Would have liked to see Sukapon on the roster
Some sort of nod to Nintendo's first try at a fighting game other than a sticker, preferably a playable character.
- Toon Link is a clone of Link
While it would have been foolish to think he WOULDN'T be a clone of Link in some form (seeing as they are different forms of the same character), I also expected Toon Link to have things from Wind Waker/Phantom Hourglass like the Deku Leaf.