Let's see..
It was pathetically easy. I mean, I had more trouble with KH1's Normal mode than Proud mode, but I've heard from some that Proud is harder. Even still, KH1's Expert mode pwns Proud mode ten times over. Am I over exaggerating? Yeah, I probably am, but even so.. play through Expert and Proud at around say and try to take on the final boss at level 55.
I took on KH2's on level 56 and KH1's on level 55. Sure, I was further along in KH2, but it's only one level. Nevertheless, I pwned Xemnas' ass, but Xehanort's Heartless was a pain in the ass. Trust me.. if you're level 55 and your defense is 34, when he says "Take this!" you better start dodge rolling out of the way. For me, it was a four to five (If I was using Aero.) hit punch. Oh, and those lazers.. damn.. They were so annoying lethal at level 55, even with Aero, which I recommend if you do a low - mid level run. It's a life-saver, in KH1.
What else? Oh yeah.. as said before, magic is pretty much useless. The only purpose I found was ending a battle asap, beating the "I'm charging my laser" section of the final boss, Cure, and Reflect. Beyond that and those two spells, there was really no other purpose. Btw, I hated how you had to either use a spell or complete a combo to end a boss battle. Sure, I want to have to use spells, but not just to end a battle asap.
Drives, though a cool idea, where relatively unnecessary and pointless. If only they could of beefed up the enemies and/ or had a way to make them more powerful by the level, thus giving Drives a point. Actually, if there's two keyblades, then why is your attack power not going up all too much?
Reaction Commands, though another cool idea, especially if it was more well thought out, are also relatively pointless.. most of the time. Where's the penalty in jamming Triangle until it pops up? Why are they almost always mapped to the Triangle button? Why not on the Command menu more.. or on other buttons? There's so many ways they could of been done better. It looks like BBS might be taking the cue, seeing how I recall seeing circle being used for one or two of them, instead of triangle and triangle was in there to.
Finally.. (I got more to say, but I'll end it here.) the story sucked and failed at being connected. That is all.