I have been getting by on 35s with a mild 4-5" SAS setup with just improved birfields and 5.29s and a 4.7 t-case. We daily drive it and use it for the exact kind of thing you have in mind. 35s seem to be well within the mechanical limits of my setup, I hardly ever break anything unless I get stupid and its good on any trail I throw it at, good on the highway and long trips. I get 19-21 mpg most tanks and I have goten up to 26 mpg on a long trip with a 3RZ engine swap.