My favourite combo at the moment needs a Warlock to help, while Hunger of Hadar (Warlock spell) is great on its own for slowing down a big horde of enemies if you then have another caster add Sleet Storm which has an even bigger AOE it becomes another level of calamity.
Now that's what I was looking for! Combining Hunger of Hadar and Sleet Storm! I would have never thought. I wonder how that looks in the battlefield ^^
Be careful learning them all too quickly, At level 9 I had learned everything possible from scribing scrolls I had collected and when it was time to level up to 10 I couldn't as the game wants you to choose 2 spells with no option to skip it.
Now I just ignore a lot of the junk spells I'd never really use to make sure I've got something to pick at level ups if need be.
I am in no rush! I mean whenever I find a scrolls I learn it, but I am not looking to find more scrolls. If they are in my way I collect them haha