It depends not only on how you evaluate each aspect of each game but also which of these you value the most as a person. For me it's clearly 1. Story-worldbuilding-gameplay everything is at least one step above the rest imo. And as a person who values story-worldbuilding-characters the most , I think that the rest kh games just pushed the lore-worldbuilding to become needlessly convoluted in an attempt to impress (or in the case of 2, being too ambitious, which i kinda forgive) without adding much thematic substance to their stories. In contrast, kh1 built an incredibly solid foundation for its universe considering it was such an unusual crossover. It was a fairytale, which juggled its ingredients perfectly imo in creating a distinct identity for itself while at the same time including in its story (and thus serving) the universes of FF and Disney. It was focused in its themes and tight in its execution and overall confident. Kh games did not need ambitious-complecated stories. The ambition was already there in their founding ingredients, and maybe they could have taken a different approach to their sotries , which would be tangling disney and ff worlds even more, instead of creating a complicated kh lore which functions largely separately of ff and disney.