If you get a few shadow potions, you should be able to use one right away, hide in a corner and cast area effect spells that do not need a target so you don't become visible. Hell Spikes level 5 would be quicker than level 2, but with enough restoration potions you shouldn't have a problem.
You can cast Aura of Command on the death knights that Josephine summons.
Can you could finish off Iona's dungeon, or something, to level up and put a point in Deadly Gift?
Corinna or (sometimes) Mpenzak in Verdistis occasionally sell spell books, in addition to Kistandalius or (sometimes) Blake in Ars Magicana.
If you quick save before running your mouse over an item/chest/merchant or hitting the alt key, you can identify the item or trade with the merchant, then quick load to get different stats or inventory. This can be done repeatedly to get the best stats or specific bonuses on an item (save after finding good candidates) or looking for specific items (such as spell books or charms) from merchants. Don't waste too much time with this, though, it really isn't necessary to get the best possible equipment.
Or the easy way to get another skill point;
iZakaroN's SaveEditor (or from
Kiya's site, with description)