The S series (1700, 1900, 2500, 2600) Internationals wouldn't be too fun on a long trip. The newer 47 and 4900, along with the 8100, 92, 93, 94, and 9900 would be pretty good choices, but not a lot of single axles out there in the 9000s. A daycab version of just about anything out there with a factory sleeper would be OK. Freightliner Centuries, Columbias, FLDs, Pete 336, 378, 379, KW T300, T600, Mack's traditional small cabs, like the R models, even older ones, aren't all that tight of a fit behind the wheel. Don't count out the square-nosed Petes and Kenworths. The later ones turn a lot better than you would expect them to. Also the Internationals models that end in an "I", on the 9000 series trucks, which came around about 2000 I think, have a curved windshield instead of flat, and the dash won't hold anything that's not secured, but the climate control is a lot better in them, and the wheels cut a lot farther for better turning radius.
I'd avoid Cat motors, too. They like their fuel more than the Detroits, Cummins, and Mack/Volvo's. Especially the ACERTs, the bottom end will last forever, but the top end has a lot of problems, especially valve actuators. And they take special tools to even just lash the valves.