Glad to see another FF fan on the board.
The reason why I have FF8 at the lowest, is for the following reason:
1. Draw system was horrible in my opinion. I had no joy in drawing magic, it felt boring/repetitive and didn't add anything to the series. Probably the single worst magic system I've seen in an RPG.
2. Multiple character stories. When playing an RPG (or any game), I like to play 1 main character. Switching between characters/stories always turns me away from the game (one of the reasons I don't like FF13 as well).
3. The story seemed a little bland to me compared to other FF games. Squall was a pretty boring character, but the rest of the characters were fun and good.
The graphics/music were pretty great for the time, but graphics/music just don't compensate for the, in my opinion, horrible magic system, bland story, bad main character and multi-character story.
All of the above is just my opinion, of course.