Chances are, you did absolutely fine. The only way Scholars can use too much MP is if you use Adlo to heal mostly instead of Physick, or if you're spamming Succor - but if you're using Succor a lot, it's most likely because you need it, from AoE damage being taken.

Like some other people have said, one of the biggest things is managing Aetherflow. Say you just started a fight, and you have three stacks of Aetherflow, and Aetherflow is also off cooldown. Once you start to dip to around 80% MP, use Energy Drain once or twice, maybe Sacred Soil, Adlo the tank and Succor the rest to burn a bit of MP. Make sure you use all your stacks, then pop Aetherflow for another three stacks. You should be back at 100% MP and ready to keep healing.

This will work even if you're down to 50% MP or so, popping all three Energy Drains even without Cleric Stance then Aetherflow will push you to 80-100% MP. That being said, it all depends on the fight. If you KNOW there's some random heavy damage, or your group takes a little more damage than they should it's smart to keep one or two stacks of Aetherflow for Lustrate, unless of course Aether is off CD.