I'm too lazy to read everything and get involved in the argument (plus I just got Xenoblade which will soon distract me from absolutely everything else). BUT...
Wait, wait, wait... what? Gameplay is important as long as there is any. Even if you play a game for its story and character design, you will still have to make it through the "gameplay parts". If you have to spend, say, a total of 12 hours making it from boring point A's to boring point B's and button mashing X to make it through boring battles that have no impact on you, then that's certainly just bad for the game as a whole. On the other hand, exploring interesting places and enjoying intense and interesting battles will always be a great plus. A good story and good character design does not automatically mean any and all gameplay flaws are forgiven.
...this is, for example, the sole reason I really didn't like Xenosaga 2. I could accept the new character models after a while, but the terrible battle system just killed it for me. I did, however, love both Xenosaga 1 and 3. Because I found both of their battle systems totally fun and awesome. So yes, that "small" difference in gameplay was the deciding factor that made me love 1 and 3, but not 2. If you are playing a "game", then the gameplay will matter. A lot.
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...anyhow, the best track from the Xenosaga series is obviously Promised Pain. It's so epic:
https://www.youtube.com/watch?v=fv7c0si2AEo