Bigger Tires for 15" Access Cab

Currently I'm running around 50k miles on some 235/70/15 Destinations (2011 2wd Access Cab 5-lug) and will probably need new tires soon. I wouldn't mind getting a slightly bigger tire to fill out the wheel well a little more and offer a small "lift". I was thinking 235/75/15 but what do you guys think? Could I go bigger? I'm trying to figure out how much room I have to play with without modifying anything.

Currently, my speedo is near dead accurate according to my GPS. I wonder how much it would change. And I have played with the sticky tire calculator thread some, but simulated visualizations don't offer the perspective of pics and or other thoughtful insights from the TacomWorld community

 

Friendly bump. Also opened to brand suggestions for P-rated shoes. I see 70% highway, 20% city, and 10% off-road (not wheeling, just off the beaten path here and there). I have my eyes on Falken Wildpeaks A/T3W and Cooper Discoverer AT3, but am unsure if those come in P-rate. Thanks for the help!