I'll take a shot at it.
YES!
-
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- Online mode is good for practice
- MASTEEEER COOOORE~! <3
- Much more balanced than previous games
- Faster and more exciting than Brawl
- Custom moves
- Smash Run
- Great stage selection, in particular Kalos Pokémon League, Town & City, Arena Ferox and Boxing Ring
- No character feels
too good or
too poor
- Music player is a godsend
- Can listen to music on the go
- Challenges are fun and diverse
- Plenty of game modes
- DLC
- Pretty graphics
- Plenty of replay value
- Keeps fresh with new fighters and series
NUH-UH!
- A lot of the game modes aren't actually all that fun
- Smash Tour is immensely sub-par
- Omega Mode limits For Glory
- Wolf and Lucas are missing
- No option to toggle on / off stage hazards
- No option to play with customs without equipment / vice-versa
- Some challenges are just obnoxiously hard
- Some characters feel imbalanced (Little Mac, Donkey Kong)
- Could use more content from Metroid, Donkey Kong, Wario Land, newer Kirby, etc.
- Bosses are intrusive
- Online is spotty at the best of times
- Why can't I send messages online?!
- Some items are just broken (Gust Bellows, Beetle)
- A lot of characters are poorly or unfairly depicted (Wario, Little Mac, Ridley, Chrom)
Otherwise I'm good. :3