Healing and Tanking are awkward in savage content. Even with tank mimicry and Mighty Guard up, Blue Mage takes significant damage from autos such that the healer basically needs to be using Pom Cure every single GCD. You basically have no real tank cooldowns on BLU other than Diamondback, which is virtually required for almost all tank busters (unless you stack Gobskin, Devour, and Bad Breath). They should add a defensive cooldown property to Veil of the Whorl to make it like Vengeance, and add a few more defensive cooldowns as well, including one that permanently buffs Physical Defense/Magic Defense. Even though Mighty Guard+Tank Mimicry grant a high amount of mitigation, the base damage BLU takes is high because of the pathetically low base defense they have as a DoM in caster gear. I think they also need to add a Regen skill.

The biggest flaw of tanking on BLU in savage is tank swapping. It requires the use of Frog Legs which is an AoE provoke with a decent range (8y) and it doesn't have bonus enmity attached to it like a real Provoke either. It makes fights with multiple targets a real pain in the ass.