I work for a pax regional, and I love my job. I also worked for a cargo regional, and I know it's different from the big guys, but I've seem both just the same. If you asked me now which I would choose, I would say cargo, by a thin margin. Mostly because I just like to work at night. The flight attendants can be fun, but now they lock them out during flight, and they can be just as much of a pain as they can me an asset. Cargo never gets sick, or complains about thier connections or turbulence, and they rarely hijack you. Of course, pax guys never carry hazmat, as cargo guys do.
Once you have your career job, the flight time per year doesn't matter as much, so it really is a matter of choice. I know a lot of guys who wouldn't even apply to a cargo carrier, and some who prefer cargo, and still others who will take either. I guess I'm in the last category.
Hope this helps, and good luck in your career.