The only class I'm really unenthused to play is WAR, but it's not a mechanics thing.
I just ... don't dig 2h Axes. I even bought the Blackbosom Scythe, got WAR to 70 ... then realized I would never have another weapon choice.

(And to those who don't like BLM due to long casts... from my experiences at 70, once you get some spellspeed rocking, it's not so bad. Although, you are forever going to be a healer sponge. Heh.)