Kingdom Hearts 2 is a strange game. For having come out 2 decades ago, it's still far and away the best game in the series (not that there was much competition). And then astoundingly, the final mix version makes it even better.
From the minor tweaks like new abilities or cutscene changes, to the major changes like entirely new drive forms and a dozen new bosses, Final Mix goes out of its way to make a good game even better.
Given all this praise, me giving FM the same score as the original KH2 might seem strange, but it really comes down to the fact that at the end of the day, its still just a tad too simple.
KH2's critical mode is often praised as the peak of a balanced challenge in the series. And while I admit that it's far better than 1, BBS, or 3's hardest difficulties, KH2's critical mode is still a breeze to play through. Despite being 15 levels lower than my base game playthrough, I still made it through the game with very little hair pulling. Did I die more than the original KH2? Sure. But they were all to bosses that were tougher in the original game too, like Xaldin or Xemnas. Had the numbers been scaled down, I can't say that I would've been challenged at all. Though perhaps this is my fault for having gotten so good at the series in a relatively short span of time.

KH2 FM is fantastic, and while I weep for the fact that this is where the franchise peaked, I'm still glad that it peaked at such a height.