I think everyone could agree with me on this that blue mage needs a complete rework and being made into a properly functioning job.
Since there is unbalance in the number of classes, what if we turn blue mage into a dps oriented healer?
Making it a pure healer wouldnt make a lot of sense from design perspective, so maybe SE should experiment with a healer that could do damage and heal at the same time?
With abilities similar to warriors nascent flash, where warrior deals damage and he heals other party member with it, blue mage could have something like that too and have some healing skills as well. Blue mage could also have some team mitigation tools or damage reducing spells too to make it all more diverse.
It will be something different to play and game would use some more healers.