From my experience with the game thus far, I think the casters are by far the hardest to play mostly because of the travelers and elven enemies that can wander through the starting zone. They're pretty much a death sentence at the first few levels mostly because they will relentlessly pursue you. On my warlock runs I've consistently had to escape to the upstairs in Mansfield and sleep/hide until what was on my tail wanders away far enough to poke my head down. It works, but it feels scummy and isn't satisfying :P Fallen Knight, Nomad and Inquisitor had no such troubles for me except for running into casters, and the casters seem to have much less in the way of stamina to give chase to you with.
Do enemies actually have levels or are their stats predetermined/abstracted? I ask because being able to look at an enemy with shift to evaluate an enemy's relative power level to your own might do a lot for easing new players into the experience and make the button more useful beyond seeing if they have goodies and character fluff. I can see how it'd be really hard to tell if something's gonna end up stomping you and how exactly said stomping occurs. Something like Caves of Qud, here
Where the Impossible describes the creature's strength relative to yours, neutral describing the creature's disposition towards you.
All that said, I like the idea of alternate starting zones which breathed much more replayability for me into games like Qud and C:DDA. Maybe some generalized start locations for all types of characters, and a few that are race/class specific? I feel like after enough playthroughs and without any natural evolution of your starting area, that zone is going to get stale fairly quickly. Maybe some reason to go back to "where it all began?" :)