Just finished Yakuza 2. Damn good game. Why aren't more games like this? I don't know. But yeah, it's definitely a keeper. I didn't get to spend anywhere near as much time on side quests and stuff as I woulda liked, because I was trying to get the game finished in a weekend, and that's not much time at all. So I'll probably go back to this sometime soon-ish. Can't wait for Yakuza 3. Sorta can't wait for Yakuza Kenzan... eh, I can wait for that, actually.
And Arcana Heart would be better if A) It didn't play like shit. Actually, that's all it needs. If you want a girlie fighter, there's already Melty Blood AC, and it's way better.
Darth, once you have KOF XI, GGXXAC, and SF Anthology, I think the last good domestic PS2 fighter you'll need is Street Fighter Alpha Anthology. Which has Alpha (which is boring), Alpha 2 (which kicks ass) and Alpha 3 (which kicks slightly less ass, but still copious ass.) There's also Pocket Fighter on there, which is a pretty damn fun game, as well as tweaked versions of SFA2 and SFA3.
Edit: Y'know, and now that I think about it, thank God for Sony. The same regulations they had that allowed for Backyard Wrestling almost made Yakuza 2 a permanent no-show in the US. Thanks, guys!