And here I thought you could use a break.[ Caster grin flashes teeth to Waver and without warning resumes his work. He is careful, but he also prefers to work quickly, rather than slowly— no reason to draw out the already unpleasant experience ]

You could try with Evocation and Transmutation lectures. They both have a lot of practice early on and you can see the effects— [ or lack of them ] —clearly. One manipulates energy, the other manipulates matter. Both are not that different from what Servants could do.

[ As manipulating mana provided by their Masters, and going from state of pure energy to solid matter, could be likened to that. ]

Once you get a hang of basics with those, Abjuration could be good choice as well, its focus mostly on will. [ See, even if he focuses his studies on few narrow fields, he napped on all classes. As he runs the lectures in his head he remembers something— ] Kiddo, you both could benefit from Alchemy. A lot of easier concoction doesn't require magic, only being able to tell what magic ingredients possess.

[ Which Iskandar should easily do. It's a sudden idea that struck him, because he imagines a magus without magic... probably not a favourite place to be. And while alchemy cannot really compare it's a substitute, a compromise. ]