well, if your off-roading will be as you described, you're perfectly set with base. That's what I have and so far I didn't need locker. I do use all gearing that I have in my base, including low range lock on some steeper hills where I wouldn't get through otherwise by any chance. I upgraded tires to 33" M/T, and installed rocker panel protectors. I do light off-roading, mainly Joshua Tree area, with some rougher spots here and there but never any problem.
However, I do regret that I don't have ADV (didn't think of it in the time of purchase) because I'd feel much safer and would tackle spots that I currently avoid from fear of getting stuck (I off-road solo)... you can check my pics in the image section to see the actual terrain.. I'm planning to upgrade to '09 with dual lockers I guess at some point and then keep the vehicle forever, or maybe get H2 if I'd find a good deal; but I really like my current truck soo..
good luck with your choice!
here would be pics with some of my typical terrain, also, while climbing that hill there I could see sky only through the windshield later during the climb, not crazy steep, but still fun hill to drive up:
http://www.elcovaforums.com/forums/s...ad.php?t=34734