BLM's MP is a huge part of their gameplay. The point of MP for a BLM is to throttle their Fire phase. So, it's kind of silly to include them in this discussion.

SMN can run out of MP if they're not paying attention and you can easily rez 2-3 times (or be rezzed once) and be in a "not so good" state whenever it comes to MP in larger group content, same with RDM.