If you want to travel outside the US...
I would seriously suggest staying away from newer diesels in general...
Thinking, simplicity, reliability, ease of access to parts.....
I would start with the 12v cummins... simple, 1 wire, no fuel restrictions. They are used in almost EVERYTHING, marine engines, agriculture, generators, etc.... so, parts are pretty readily available. Its an efficient engine....
The Ford 6.9/7.3 IDI... mechanical injection, not complicated, pretty reliable... used in school buses, which, usually end up being sold to other countries, which, helps with parts availability....
The 7.3 PSD. I put it at the bottom, for no other reason, than the electronics, and complexity. I had 2, loved them, no major problems, not too thirsty. Its a great engine, and wouldnt hesitate to own one again....
I am just a firm believer in simplicity. These trucks get VERY heavy.... a typical diesel p/u, with 35s.... you arent going push that... yes, a winch is needed...
I use a hydraulic winch... its argued, that the engine needs to stay running, yes... but, you need the engine running, even with an electric winch.. you arent going to pull much on the battery, alone..... just MY thoughts.... and my hydraulic has a 100% duty cycle.... it can pull all day..(nice for dragging logs, and fallen trees).....
Anyway, I would also look strongly at a manual trans.......
Just keep your selection simple.
You can travel the world in a suburu, or a ford escort if you wish...
Its all in how you wish to travel, that should dictate what you need....
Chase