Now that I have a bit more time I'll go a bit more in-depth on my impressions.
I used to play Brawl fanatically. Melee too, and even the original, but I was never good at those two. Last year I went to a low-key Smash tournament thing and it turned out to be in Project M. I won the tournament, but I still fucking hate PM. I don't want to rant though, so I'll leave it at that. Anyway, I'm glad the developers made some concessions, and this game feels like a good balance between 'accessible' and 'complex'. Or, if you want to generalize, between Brawl and Melee.
I was pretty bummed that Smash Run couldn't be played online (even if only with friends), and even more bummed that you couldn't actually encounter or chase down your opponents in the stage (though five seconds of thinking that through reveals why -- with powers and a speed stat to keep up with disadvantaged players, things could get nasty. But Kibry Air Ride allowed you to fight your opponents while gathering powerups, so I was hoping for
something like that). I was most bummed, like extraordinarily bummed, by the inability to change the time limit from anything but five minutes. I want to get all my stats to 1000 and run around, damnit! Once I get someone to play Smash Run locally with though, it should be a great alternative to just straight-up smashing, and fighting the impressive roster of enemies to gather
big honkin' powerups never gets old (to my OCD self, anyway).
The controls work well for what they are, my only big complaint being those damn unintentional wall clings. The input to do it is a bit too easy, making for some annoying situations.
Classic Mode is fun, but I was hoping for the enemies on 9.0 to have a bit more sting. The 9 AI was never crazy great in any Smash game though, so I guess it can't be helped, but since it's a carry-over from KI:U, I expected to die in three hits and lose all my gold. Master Core is definitely tough on 9.0 though, which is good.
The music is great, which shouldn't be any surprise. The Smash arrangements have always been top-notch. I was a bit underwhelmed by the the Final Destination theme (a remix of the otherwise good main theme). But I'm so glad that Shulk exists so I can listen to Xenoblade's superb soundtrack. I hope they'll have some more of the good ones from that game in the Wii U version.
Global Smash Power would be a lot better if it told you how many players it was out of, so you could know if you were close to the top or not. Anything over 1,000,000 generally is pretty good, but I'd still like to know the specifics.
Street Smash is a nice diversion, as are: completing the Challenges lists, playing Trophy Rush, or trying to get kills in Cruel Smash (I've only ever managed 4 before, and it was through AI screw-ups). Overall, there's a lot of stuff to do, and take all my criticism with a grain of salt because I actually have played this game for hours and hours and hours and am basically just whining about small stuff at this point.
I really like it. The controls were a bit weird at first, but I'm warming to them. I like that the "adventure mode" was replaced by "smash run", which I find much funner.
Also:
Little Mac rules.
Strange - I checked my Little Mac record for Home Run and I had 2,891 feet with a GSP of 1,109,789. So either the feet-to-meter conversion isn't the same as in real life (904.6m ~= 2967 feet) or GSP is different across regions. I guess that shouldn't come as a surprise, but it is "global"...