I really like the TJ Rubi and think it would be a reliable vehicle for world travel if a few things were modified.
Well from my experience with Jeeps, reliable isn't exactly a word I would use to describe them. Fun, tough, capable, sure, but reliable, no way. Maybe an old Land Cruiser.
As for issues with "keeping them tuned" etc, remember, you're talking about going out into the middle of nowhere. Do you think the local tribes are going to have a code reader to tell you why you computer equipped vehicle is in limp mode? Nope, but if your carb screws up, you unbolt it with simple hand tools and disassemble it, clean it out, and put it back together. Even if you simply go to fuel injection you are complicating things to the point where parts would simply not be available (crank position sensor (?)). For what you are talking about, you need a capable (mild lift, good tires, lockers, winch, hilift, at least 2 spares, extra water, oil, gear oil, welder, air compressor just to start) rig that is as simple as possible. That means carb. A FI vehicle is much more driveable and comfortable, but a carbed vehicle can be rigged to run with much more primitive fabrication. If you want something you can rig up with welds, bailing wire, and duct tape, you don't want ANY unneccesary electronics, and you don't want anything to be more complicated than it has to be to make the vehicle run.
(flame suit on)
And the LAST vehicle I would want is anything made by Chrysler. Not trying to offend anyone here. My AMC Jeeps won't be winning any awards for reliability either, but Dodge/Chrysler are and always have been total crap IMO. One could say the same about my AMC's and I'd agree with you, but that doesn't mean I don't love my AMC's, it just means I'm honest with myself and others about them.