Picked it up yesterday or earlier today, can't remember, and have been playing it in spurts since I got it. Haven't made it past level 4 yet due to stupid mistakes/evil enemies playing with traps.
Yeah, level 4 is my wall so far too. Furthest I've gotten so far is with a Promethean magic build with vampirism thrown in because I felt like it. It was surprisingly effective, actually. Promethean magic has very strong AOE spells, and vampirism allowed me to heal on the fly just by hitting stuff with my staff or from one of the many corpses my Fireball spell created. Even with crappy armor it was a pretty big survivability boost.
My latest build has dropped Vampirism in favor of Archaeology though. Traps were the real weakness of my previous build (and what finally killed me on my previous build) since Vampirism characters can't use food to heal, and Archaeology should help with that. Oh, and the ability to recharge anvils is nice too.