~The fact that I'm not playing it right now. Nintendo could manage a worldwide release with Pokemon, so this is a disappointment for me. Probably the biggest. But, it is pretty standard.
~The clones aren't a bad thing at all. They are not a waste of development time, they are a result of extra time. They are bonus content, and I like them. But Dark Pit is too similar. This may only be due to our lack of knowledge about both Pit and his clone, but the lack of obvious differences is jarring.
~Music restrictions. 2 songs per stage? This would be enough if they hadn't recycled so much Brawl music. Why does the Fire Emblem from Melee and the final boss music ripped straight Awakening play on Arena Ferox? Why not the song that actually plays there? Why not a redone track, like the many they did for the many Mario stages? No redone tracks from Xenoblade is annoying, but they are good enough tracks to stand on their own.
~The stage list is all over the place. The new to old stages ratio is too even. No new Yoshi or Metroid stage, but The Mario series has what, 5?! At least there seem to be enough legal stages to get by, if you get generous.
~Blast zones in general seem too big. This may not be that big an issue, as we haven't really sunk our teeth into the gameplay yet, but it's a bit disappointing.
~Costumes are a mixed bag. On one hand, characters like Charizard, Jigglypuff, Lucina, and Rosalina have great costumes. On the other, Wario and Olimar/Alph got screwed with 4 colors for each costume, while Little Mac gets 16. It's these inconsistencies that disappointed me most overall.
Don't get me wrong, overall I love this game! The roster is great, despite losing some guys (RIP in peace Ice Climbers). I never thought I would get Robin, Shulk and Palutena! The demo is super fun, but I crave more. Gimme the game, Sakurai! I NEED IT!