I've had a pure-mage character before and worked pretty hard on it, reaching level 100 in Destruction Spells but... they feel so weak. Like really, the spell Blizzard, it's not easy to get and when used it does more damage to the items in the cave than the enemies I'm fighting. Sure, if you manage to find a scroll for it and use it at any level below 30, it might kill your enemies but when you actually own the spell, which for me was when I was level 50 or so, the enemies are a little tougher than before. Not only does it not kill any enemies anymore (for a bloody master spell it should kill all my enemies) but it's also so bloody slow; it requires two hands to cast and it takes like 7 seconds or so to power-up, by then every enemy in the room has probably hit me 3 times each and being pure-mage my armor isn't that great either, I'll probably die before getting to use it.
I request that Master Level Spells get tweaked and maybe add a few more.