The only problem with making Blue Mage a limited job was pretending like it's a job. Blue Mage is not a job, it's a side attraction on par with things like Firmanent or Island Sanctuary or any sort of optional side content to go do for fun. Putting it on same list as actual jobs and such was the real mistake with it. The limited jobs are a good and fun idea, but they should never have been called 'jobs' because excessively whiny people in community will use that as excuse to have it be made into a 'real job' which can only ever happen by removing everything that makes Blue Mage unique (and yes, it will HAVE to happen, regardless of your thoughts on current job homogenization, Blue Mage would have never fit into the game at any point in its history, past or present, without being reworked from ground up and homogenized to at least somewhat fit into existing roles).