The company truck I drove, (Ram 2500, ext. cab, long box diesel 4x4) had a lot less power assist than the Grand Caravan I'm used to driving. I know it's 2000 lbs or about 50% heavier, but the steering effort required was 2-3 times more, even with proper fluid levels.

I might be interested in a 1/2 ton truck and was wondering if the steering would feel much lighter on a 1/2 ton gas-powered truck than the 3/4 ton diesel.

That was one of the few things I did not like about driving the truck; my arms would get a little tired after a while from plain easy-going city driving.

Well, the older 1/2 tons like mine are "trucks" as in the olden days. The newer trucks like the new Silverado is basically a car with all the creature comforts that you can take off-road ...sort-of. Even in the new Silverado commercials you see the front bumper is clearing the rocky road by an inch here or there between rocks. I would not take a factory rigged new truck very far off road personally, not without a good tow strap, a charged cell phone, and a phone number for a tow truck outfit, or a buddy with an old K5. Factory "trucks" from the '70's and early to mid 80's you could throw in the mud or off road and feel pretty confident about getting back out. Unless you got into a situation with one wheel completely off the ground without a locker in the diff. "limited slip diffs" should be classified as "do you feel lucky diffs" in my opinion. Most of the time it's just a 'feel good thing' that don't work for *** in the real world.
I don't get the armstrong steering fatigue driving my beast but then it's not a yuppie truck either. You can't have it both ways my friend. Have you seen the 4wor article on installing a high pinion Dana 60 straight axle on a new Silverado ?
12K is a pretty steep price to pay in my opinion, and you still end up with the weak frame and weak components of a 'new' truck.
The reason Chevy doesn't come with a factory straight axle in front is very simple: They don't break very often. On the other hand Chevy makes a fortune in IFS axle parts replacements - simple economics - It's designed to break from the factory.
"4X4" and "Off Road" are just sales slogans today's trucks. - just my opinion on this stuff, dude.