Magic won't be added in until post-release, but is planned.
Micromanagement is not too intensive compared to some other games, but definitely can be the difference between winning and losing. Against an NPC, it's pretty easy to just rush for the most part. PvP hasn't been enabled yet, but I imagine it will be much different against a human opponent. There are "hard counters" so it will be important to micromanage your units so that they're using their strengths to their advantages.