From personal experience, you can't go wrong with the BF Goodrich All Terrain KO. While it's not a hard core off road tire, it does do very well off road, and so far, it's th best snow tire I've ever used. I have a set in 235/75/15 on my other truck (S10 Blazer 4x4), and didn't even use the 4 wheel drive last winter. They seem to have decent road manners, not too noisy. For what you're doing, I think a 30x9.50 or 31x10.50 will be just fine, maybe with a mild lift (1 inch or so) if the fender clearance concerns you. Up front shouldn't be an issue. You could get away with a 15x7 wheel, but a 15x8 would give better handling and sidewall support.
Disclaimer, yes, I do work in a tire shop that sells BF Goodrich tires. No, I'm not plugging the business, only relaying personal experience with the tire in question.
