Maybe it's just me, but I found X to be pretty physically linear too, apart from the occasional open space (and even then there wasn't much to do but get to the other side).
As for the battle system...that's kind of why I play games. I can enjoy a game with not so great gameplay if the story is really good, but it works the other way too (FFXII).
As for the music, I haven't listened to the entire soundtrack, but I've enjoyed pretty much all of what I've heard (The battle themes, main menu theme, and a few others).
Sorry, I know it's stupid that I'm arguing the merits of a game I haven't even played, and it really just comes down to personal preference, but it just doesn't seem like such a bad game to me.
Edit: I really don't know too much about the plot aspects, and those could absolutely be terrible, the other stuff doesn't seem so bad though.