Go with the largest size tire you can afford.
So, lets say your 35" tire choice. What will you need to do to run this tire? You can get a budget boost of some kind that will give you just enough clearance after you trim your flares to run 35s. The added benefit is the lack of flex you will have. You don't want a smooth ride do you? If a smooth ride is what you desire, well you can get a lift with quality components at about 2500 dollars its gonna be awesome. Oh wait, you will need to get new driveshafts possibly, maybe new wheels with porper backspacing or wheel spacers. You will probably want to gussett the axles. Regear the vehicle to make it close to stock on the highway. Good luck.