Its fun how you put blue mage in dps roles when it has been one of the main support roles in most ff titles they have been in :P

Adding blue mage is more work than you think. Adding ONE skill means adding animations to every race, every class able to use it, adding light effects, buffs, balancing. Etc.

Also, blue mage should be a class, and they use sabers or guns, not swords. Its like saying that a fencer uses a sword :P