So I was disappointed by the info on Blue Mage and thought I would list how I've always thought it would work, along with one of the other jobs they mentioned that might be a limited job in the future. (IMO Beastmaster and Puppestmaster are kind of the same thing just with different skins. Huh, sounds like Blue and Black Mage. (Both cast spells just different names.) Anyway. Be gentle please. I'm not a game designer.

Blue Mage

Unlock Quest: You help your mentor with a dangerous mob. Mob uses a move that hits you, you learn the skill. Mentor notices and offers to teach how to use monster skills back on them. Blue Mage unlocked.

All skills come form job quests that send you out to fight 1 or 2 mobs and acquire their skills by either seeing them or getting hit by them depending on the mob.

Blue Mage could have some party damage mitigating effects such as Mighty Guard to mitigate a very small amount of damage for big attacks or tank busters, and small party heals to help Healers in time of need such as White Wind. Abilities that cause status effects also deal some damage to not make them "completely" useless on monsters that are immune to the status effect.

Beastmaster

You get one pet.

Your physical skills chain into and empower your pet skills that then chain into and empower your higher tier skills. Pet could have roars that empower the party such as damage up or defense up.

Pet doesn't have it's own pet menu like Summoner does. Instead the skills are treated as your skills but the pet does the actions. Pet auto attacks at the same time you auto attack, will not chase monsters and stays close to you.