Summoners could have a Cleric Stance that merely switches INT and MND without the damage and healing percentage changes. That would simplify the issue for everyone, and would be in line with the mentality of the armory system in the first place. It should be an early level Arcanist skill.

You could call it "Arcane Stance" or maybe "Primal Stance."

For me it'd be great. I often queue for the Duty Finder as a healer for the express purpose of lowering my wait time. Sans this change, I'll have no choice other than to level White Mage. For now that'll be what I do, but it's a shame to have to do with that while still leveling.