The "cruise control" feature for rough terrain is also in our Tacoma (called "crawl mode"). It's pretty amazing, especially in the lowest gear. It makes some strange noises which I believe is basically the anti-lock brakes going on and off, sometimes many times a second. I'm new to four wheel driving, but I'm amazed at what it can do by preventing wheel slippage. It seems like it's just a software thing with the anti-lock system, which is clever and I'm sure the manufacturers are enjoying selling the feature at little cost.
I'm almost wondering if a locking diff isn't really necessary, although we've used that too a couple times when we did NOT want to slip. There was one steep ridge where I was a skosh nervous about slipping, or stopping, and really wanted to make it up to the top where it wasn't white-knuckle driving any more. That's when the rear locking differential gave me some confidence. However, the truck seemed to go up like it was no big deal. If we'd slipped part way up and trended to one side or the other, or had to back down... well... hmmm... Anyway perhaps using the crawl mode is essentially the same effect on mitigating wheel slippage.
Sounds like you have a worthy vehicle.
By the way, we watched weight like a Hawk, er, Fleet, but somehow we put on several hundred pounds more than I estimated pre-delivery. We've been up to 700 lb overweight. The truck doesn't seem to care. I'm still not sure where the weight is coming from -- maybe more water than I thought, too much food, extras like compressor and too many clothes. We even took out some stuff we don't use, like the bed extender and pads, one of the propane canisters, etc. I like to weigh any time we pass a weigh station. 'Tis fun to track.
We had P tires that supposedly were plenty macho according to the numbers, but after puncturing a sidewall past Cerro Gordo on another tricky section, decided to get E tires. So far the E tires (BFG KO2) have performed well in terms of gas mileage and noise, which I thought would be worse. No problems wandering Mojave Preserve and Death Valley but our experience is limited with the new tires.