It would take a bit more adjusting then that. See Blue mages get an insane opener in Moonflute into all of their cool downs but I can't find any direct comparisons so I can't even begin to make guesses at what a flat footed attempt at balancing them would take but....I kind of also think that if it's not anything competitive, it doesn't really matter. Blue mages take way more effort than other jobs so they are always going to be niche, so what if they blow up the Great Gubal Library or the tower of Zot?