I've played all the KH games so far, and if I had to describe my feelings towards the series in a phrase, it'd be "The series I love to hate...but secretly really love." xD
KHI was genuinely fun. It was one of the first games I played on the PS2, and I was really excited about it. I suppose you could say it was my gateway drug into gaming (before it I had only played Mario games on N64, Pokemon, and those stupid little Barbie games), so it'll always have a place in my heart. I enjoyed the storyline and was really interested in it, the gameplay was challenging at times, but I got through it well enough. Still haven't beat Seph, though. =p
The second one. I found the gameplay to be much easier than the first, with the addition of the forms and the triangle button and all that. And just in general, it was easier. I actually managed to beat Seph in this one. KHII was also when the storyline started getting all convoluted and twisty. After I played through it, I still loved the series, but I was starting to look at it like, "Oh, this is going to get really complicated really fast, and I'm not sure if I can keep my straight face." My favorite part was when Sora cried after finding Riku. I almost lost my shit. After that, it was too easy for me to tease.
Uh...Re:COM, the card system to a bit to master, but once I did, I didn't mind it at all. 358/2 Days was immensely enjoyable, especially the multiplayer. I love playing as Saix and Axel. And the different weapon forms for all of them is awesome too. BBS was also really good. I especially like how it has a theatre feature, so you can go back and watch all the cutscenes, because you will need it by the end of the game. Re:Coded, I'm still playing. I haven't finished it as I got distracted by Assassin's Creed, but I'm getting back to it now. So far it's fun. It has a weird kind of multiplayer that I haven't actually gotten to try out yet, because I don't know anyone else who has it, lol.
Anyhow. At this point, I'm literally ass over head confused as to the storyline and who's really who. I need to go through and do a lot of reading to straighten things out. I guess that's my only real complaint about the series, that the storyline is getting increasingly more confusing, and it seems like each new installment just brings up more questions without answering the pre-existing ones.
Everything else, I pretty much just make fun of. I can do a pretty good reenactment of the entire first game, haha. Pretty sarcastic, but accurate. xD
But I still love Kingdom Hearts. I think it'll always be my number one fandom, with Final Fantasy coming in a close second. Sephiroth is like, my ultimate idol, so I'm always happy to see him in the game. Someone I really love and super super super want to see in EVERY single KH game forthcoming is Vanitas, and there is one huge reason why I love him: he's sarcastic. He has a biting tongue and I love it. Yeah, sure, he's darkness embodied, but somebody's gotta make the snarky comments around here.
Anyhow. As you can see, I'm always up for a KH discussion, so we should definitely keep this thread going.