So this is kind of an idea I had, but it needs fleshing out. I thought that for a 2v1 game, it might be better if it worked as if it were a 2v2. What I mean by that is that the single player is treated as two players who share position and control of spells.
The single player gets twice as many spellbook points and actions, and twice as much health, channeling and starting mana. However, the single player cannot take consecutive action phases.
Alternatively, you could just have the single player control two spellbooks and two mages and play a regular 2v2 game.
Or you could have the single player fuse his mages together into one by adding all of their stats together and sharing position but having separate non-consecutive action phases.
Or you could try switching Mages in a manner similar to Quirrel format. With this option, you can, during the reset phase, choose to switch out your mage with your other mage. When this happens, all Mageclass and school class only spells that you control are switched out as well. Then all damage on your switched out Mage is transferred to your active Mage.
Thoughts?