Yes, it's ridiculous. You will have Big Game Hunter and Killer Vegan. But you will also have the Emo heal which removes curses, so kill all the diggles you want then just pop a heal! It's not that horrible of a skill set once you get some levels. The Cure is obviously an early must-have spell. The debuff really isn't a big deal. Swashbuckling is really not bad! Almost guaranteed counters for 4 turns! I might even take that over the heal at character level 2. Celestial Circle is also really good for survival. With those survival spells you can do pretty well without having much in the way of good magic. The demon pets are very helpful for opening evil chests, or fighting quest bosses. I leveled up Werediggle all the way because I had never used it, but I just don't see it as very useful. Sure you get a bunch of bonuses, but you can't cast any of your survival spells once you've committed yourself to 33 turns of digglehood. Breaking down walls is tons of fun, though. As for your 7th skill, take whatever you want. I took Archery. Probably not the best choice, but I had never used it, and I knew I could still shoot animals with bolts without getting vegan curses. The +35% bolt recovery helps a lot. It took me 4 tries, but I did win with this combo.
I tried this once, with my last skill being archaeology I think. I actually got pretty far. (Which for me is floor 3 )