What people need to keep in mind is that blue mage is, like I pointed out somewhere else, the most flexible job the FF series has, in every single aspect, be it equipment, skills, or appearance. It can be any role, especially on FFXIV, as Yoshi-P is known to change roles into whatever he sees fit. Every role it could turn into can be easily defended, but not by dismissing the rest of them, because in blue mage's case, everything is possible.