You'll need gear to make use of the 20% HP shield (or as others will say, 'Git gud to get the gear for Titan to function'). A defensive mechanic able to CC and function to make up for gear gaps? Oddly lacking at those levels on Arcanist.

Play a certain caster up to level 20 which might have an AoE CC mechanic available at level 10, get the Chocobo. Summon it. Now you're a functional glass cannon with a tank pet, an AoE CC skill and plenty of damage. I've labeled my gearset for it as "Summoner".