Wut!? Dude you are comparing a lifted truck with aftermarket protection with a stock 100 and complaining abt ground clearance and underbody protectionOP, what year is your 100? I completely disagree about lockers if you have ATRAC and want "just a little more offraod capable" that is good to go in "soft sand, snow, mud etc. only".
ATRAC works great, but IMO the biggest limiting factors on the 100 is ground clearance...it's nonexistent compared to my 4th gen 4Runner. And the cheesy plastic "engine cover" (wanna be skidplate) under the LX...wth is that? Can't imagine what running aired down does there.
My observations based on owning both an '04 V8 4Runner, and an '06 LX 470 the past 15+ years. My 4Runner has been all over Death Valley and Panamint Valley and a few places in Eastern Sierra. That's with a mild lift and slightly larger tires (265/70/17) still on stock wheels, Hanna sliders and a Shrockworks front bumper. I've barely offroaded the LX as it's the wife's pavement princess but there's no hiding the weak atributes of its poor ground clearance and poor underbelly protection.
I'm in the same boat as wanting to get my 100 at least slightly more offroadable. I'm hoping that going up to one of the largest size tires that'll fit on the factory wheels, and proper skid plates, will be all I'll need for my intended purposes of a few nights of camping/trail-running at a time. Will likely add step-sliders too. I'm hoping that the exta lift the AHC offers in 4WD will help tons on the ground clearance. Add Staun deflaters and an air tank or battery tire inflater and you should be good to go in "n soft sand, snow, mud etc. only."