BLM is my main choice. For the most part you'll be doing Thunder combos (Fire combos on groups as it's AoE), and while at it, you'll probably rarely use tier III spells for those combos due to their casting times+mp consumption VS damage doesn't really make them that worth (I personally use them to break the monotony ). Also you may find Blizzara useful for instant AoEing low hp mobs.

Other than that, I like agro management on BLM, provided you have Archer and Pugilist leveled (though Freeze does a great job too!) as well as helping with the crowd control.

Just to give you a small sample. . . .

I can understand why BLM can be dull or boring to some. There's plenty of room for improvement, of course, but I'm always having so much fun playing it regardless.