If I recall specifically, Blue Mage can do party content but only with full pre-formed parties, whether or not we can party-finder a Full Group is still unknown. specifically we can't matchmake (So no PUGs), Roulette (which I think still goes through matchmaking to pick a dugeon), PVP (way too unpredictable), and deep dungeon (I don't know why, but I assume since it still technically matchmakes you).