After recently replaying Kingdom Hearts 2, I came to realize how good the Kingdom Hearts 2 Magic System is. The game made especially good use of it by adding abilities that make use of the MP charge like when your MP is charging, your Drive Gauge fills up faster. I also used Thunder a lot more in KH2 than KH1 because it completely destroyed enemies (I used it to level up my Final Form as it killed nobodies in 2 hits). Fire was good if I wanted to A) destroy obstacles easily/destroy those carts in Land of the Dragons to level up Master Form and B) clear out any crowds of enemies around me so that I can use Thunder. I made use of Cure for not only healing(which was only 4 out of 144 times...), but to also deplete my MP and make use of the ability I mentioned earlier. I never used Reflect or Blizzard and I only used Magnet when I was in the Underdrome because it used up too much MP.
On the other hand, in Kingdom Hearts, I used Aero for some secret enemies and the Dragon Maleficent boss battle while using Fire a few times to hit some out of reach enemies. I used Blizzard to get some of those hidden chests and on out of reach enemies sometimes. I never used Thunder or Gravity except for retrieving hidden items or battling the Unknown in Final Mix (because TIP: those are the only magic attacks you can use on him). I only used Stop on the White Mushrooms in order to get that special Mushroom. I obviously used Cure a lot just for healing.
Over all, I kind of prefer the Kingdom Hearts 2 Magic System because I could make great use out of it. The last post I made here I said that I preferred the KH1 Magic System, but I hadn't played KH2 in a while, so after replaying KH2, I really saw how much better magic was.