The above post is right on target. The key to the job is letting the DoTs and your egi do their work and do burst damage whenever the chances present themselves. Don't fall into the trap of comparing your damage to that of a Black Mage. Their forte is immediate damage, yours is time-release damage with bursts in between.

As for MP management, try not to go too long between Aetherflow recharges. Also don't hesitate to use a charge to recover some MP with Energy Drain.