I think the only thing that would hold it back is more-less the Blue Mage wields a sword as a primary weapon (Sabre). So if they made Brushes and Pens that could also go up to the cap level as well as swords that Blue Mages could wield I would find the idea completely sound. But I like the idea and it is a job/class that has not been used in FFXI as far as Dilettante goes.