I've seen and done a lot of the milder stuff on 31s and a rear locker (Hells, Fins, Porcupine, Elephant Hill, etc.). Going to 33s would make a lot of trails easier (Kane Creek, Metal Masher, Steel Bender, etc.). I'd probably want lower gearing/35s/dual lockers for the more difficult trails (Cliffhanger, Moab Rim, Behind the Rocks, Golden Spike, etc.)
You don't need to go crazy to be scenic though. Do you have any trails in mind that you want to run?