If I would implement BLU in the Game, I would make him learn his skills through Job Quests where he has to go to each Beast Tribe and learn one (or more skills) from that tribe. How? Fighting the NPC who will teach the skill. He is hit by eat, and learn it after defeting the enemy. that way he would learn buffs, debuffs, healing, defensive and offensive skills/spells from that, and they could even have the element of the primal (Amal'ja Fire, Sylph Lightning, ...)