The main thing i like about FF is the storyline but i have never rushed through it, i always try to master the game while am at it.
I don't even wanna do the Excalibur II quest in IX to try to 100% master it, cause that would mean leaving other things behind which is just stupid and i wouldn't enjoy that playthrough at all.
I've mastered IX though besides the Excalibur quest, in my opinion that's the hardest one to master,even impossible (with all key-items,weapons etc.)

I think it's pointless to play FF just to go through the story, it's just half the fun.