I've written reviews of the games in this set which I've played completely through, so I figured I'd give a quick rundown of what I thought of each installment in this series:
• Kingdom Hearts Final Mix: As I said in my review, the worst thing about this game is that age has not been kind to it. Somehow, this game feels small and also confusing, as there isn't a real guidance as to where you're supposed to go, and enemies respawn constantly, a combination of which makes this game immensely frustrating at times. Yet strangely, when I just gave up and started using a strategy for this game, I ended up liking its essential elements far more. A decent beginning to the franchise, but the archaic feel of the game now isn't doing Kingdom Hearts any favors.
• Kingdom Hearts Re: Chain of Memories: Probably my least favorite game in this set, because of an idiotic move to card-based combat. In the original portable version, I'm sure this worked fine, but making cards a part of the game, while also maintaining the action-adventure style of the original game is a huge mistake. This also doesn't feel essential in the larger story, besides introducing the Castle Oblivion crew, and this game early on just lets you know that you're basically replaying everything you did in the first game. A waste of time, and I'm glad I didn't play through the whole thing.
• Kingdom Hearts 358/2 Days: An exhausting collection of cinematics, which makes you watch three characters eat ice cream over the course of a year. At least it makes me care somewhat about Roxas and Axel, but that's about it.
• Kingdom Hearts II Final Mix: A slight improvement in every way of Kingdom Hearts, making the combat better and the Disney worlds feel far more complete than before. There's also a nice amount of inventiveness in terms of worlds, be in the Steamboat Willie-themed world, Pirates of the Caribbean or Tron. But like most Final Fantasy games, Kingdom Hearts II Final Mix ratchets up the difficulty to an insane degree in the final stretch, to the point that was even difficult to me now. The added elements I think are to blame for this, as there's no way I would've finished this game when it originally came out, as it frustrated me now beyond belief.
• Kingdom Hearts Birth by Sleep Final Mix: Insanely surprised that I walk away from this set believing this is the best game in the franchise up to this point. But Birth By Sleep explains the game's lore, introduces new characters, integrates the Disney worlds beautifully, and tells three intertwining stories in a way that isn't confusing in the least, and actually clarifies many of the story's past problems. This is sort of a crowning achievement in that this series' labyrinthian story is given more context, but only makes more sense because of this prequel. I actually care for these characters, and the ideas of Kingdom Hearts actually make sense to me now. Plus the combat is fun, fast and simplified in a way I really liked. If I wasn't trying so hard to push through all these games to get to Kingdom Hearts III when it came out, I would've loved to have soaked in this one a bit more.
• Kingdom Hearts Re:coded: I can't really understand the logic of this one though. Let's confuse the story even more by introducing data versions of all the characters. I get this was somewhat introduced in Chain of Memories/KH 2, but it gets to such a stupid level that even Goofy and Donald are like "uhhhh how does this make sense?" There's got to be a way to set up Kingdom Hearts 3 without adding yet another level that doesn't really add up to much useful material.
I don't know if playing Kingdom Hearts I.5 + II.5 hurt or helped my anticipation of Kingdom Hearts III. This is clearly a frustratingly convoluted story, but this at least gave me some glimmers of understanding to grasp onto. If Kingdom Hearts III is about bringing all these disparate characters together for one final battle, I'm glad I have the ground floor of understanding to help this matter to me.
Yet I also now realize that Kingdom Hearts isn't as great as I once believed it was. This series is severely flawed in ways I didn't even remember, and honestly, Square Enix and Disney's sensibilities don't go together all that well. I still don't understand why they didn't just alter the story to make this about Mickey fighting the darkness, instead of adding Sora and the 18,000 people he meets along the way/people that live inside his heart/virtual people he's encountered through virtual simulations. It's insane.
What works for me about Kingdom Hearts are the Disney aspects, whereas the more I think about it, what I don't like about Kingdom Hearts are the same problems I have with the Final Fantasy games. There's far too much story and explanation, the dialogue is awkward, the character design is ridiculous and the game ratchets up the difficulty in the final stretch to an insane level. I almost think that if Disney had primarily made this game, Kingdom Hearts would be far more understandable and fun.
Kingdom Hearts is an interesting idea that more often than not fails in the execution of that idea, and this set reinforces that. I hope that Kingdom Hearts 3 makes all these disparate ideas and story points come together into a cohesive conclusion, but from what I've seen in this set, Kingdom Hearts is more about convolution than clarity.