Random thoughts on a few PS2 RPGs mentioned in the thread that I've played:
Radiata Stories having individual, non-generic NPCs with their own schedules, wandering around the map/city was pretty cool. It reminded me of Ultima VII for the PC, where most NPCs were unique and also had individual schedules. The story, however, was fairly cliche. Also, the replay-hook, choosing to ally yourself with either the human or non-human faction was a good idea, but the non-human side's story felt rushed and incomplete.
Star Ocean: Til the End of Time (from the same studio as Radiata) had great atmosphere, but I felt a little cheated at how the game's setting was described as a crazy-large interstellar universe, but the bulk of the story only takes place on 1-2 planets. I loved the real-time combat, though, and never got tired of the gladitorial/battle-arena parts.
I'm currently playing Kingdom Hearts 2 and the story is maddeningly juvenile, but what did I expect given the Disney content? I played the original years ago, but the combat feels very familiar, and I have a few gripes about the menu system (those extra commands have to be accessed with the d-pad which is inconvenient to do while running around the screen with the left analog stick). I mostly agree with whoever mentioned here or in an other thread that there isn't enough differentiation to merit playing both titles.
Dark Cloud is one of the few RPGs I never finished, or came within 5% of completing, because I reached the point where the monotony inherent to most games of the genre wasn't offset by any sense of accomplishment or pleasure. I skipped the sequel.
I found the first Atelier Iris to be rather charming, and kept playing due to the recipe and collection elements of the game rather than the combat or story. I have the sequel, but haven't played it yet.
I have little interest in the Xenosaga and dot.Hack series because of the criticisms I've heard (more movie than game of the former and mediocrity of the latter).
It's ironic that I'm so critical of these games' stories and yet part of the reason why I have the Shin Megami Tensei, Suikoden, Final Fantasy (starting with 9), and Shadow Hearts series sitting unplayed on my shelf is because I want to play them in chronological order to "get the full experience", but I've heard Persona 1 and Koudelka are a bitch to get through. Setting oneself up for disappointment, indeed.