That's a rather ambiguous term, "light off-roading". The factory 4x4 is fine for light off roading. Go adding in sharper rocks and IMO, ceases to be light off roading. The factory 20" wheels are plenty if you want to swap to a LT 275/65/20. The 20's still have 6" of rubber below them, the 275/65 brings that to 6.5" by going from a 33" factory tire to a 34".
I wouldn’t even go off-roading with my stock 18’s and Goodyear “AT’s”. Mainly because a flat out on the trail would mean the only thing to get me off the trail and home would be the weak spare. Then again generally where I go isn’t “light”. I suppose if if was grassy fields or groomed and maintained fire roads, I’d be ok with it