T-prop doesn't always mean "rapid upgrade". You can refer to the guys at CommutAir on that one. Their upgrade time is equal to or more than some jet jobs. Go for the airline that will offer you the best QOL in your opinion and stick it out there...try to avoid switching regionals as this only hurts in the long term (read as avoid Mesa, GoJets, etc).

"Jumpseating" is something only pilots (and some other aviation folk like the FAA, Dispatchers, ATC, etc.) can do. One could fill an entire thread about it, but the basic jist of it is, it's a way for pilots to get around on almost any airline, regardless of whether you work for them or not. Non-rev is a completely different scenario. Most regionals will give you and your immediate family (mom, dad, wife, kids) non-rev benefits on whoever your flying for. So, if you're doing flying for Delta, everyone can fly standby on Delta.

 

Depending on what she does for a living, you might want to consider moving around early in your career. I wouldn't necessarily move to the very first base you get, since there's a good chance this will be a super-junior cr@phole. Look at your company's bases, and try to pick one that is fairly junior that you think would be an interesting place to live for a while.

This will greatly enhance your QOL, and she will be happier since you will be home more often. This assumes that she is open to a little adventure, and would be OK alone in a strange city when you are out flying.

Once the kiddies and mortgage arrive, uprooting becomes very difficult and commuting begins to make more sense. If you establish a permanent home at your domicile, make sure the location has plenty of redeeming qualities...out of the five bases I have held, 3 were closed or massively downsized. Glad I didn't move...

 

1. My schedule was pretty random this month, start with 5 in a row off, then a 4 day, then 4 off, then another 4 day, then it's blocks of 2 days off. At TSA it was usually 4 on 3 off 4 on 3 off 4 on 2 off 4 on 2 off pretty consistently.
2. Some debate on the majors preference of tprop/rj pilots, generally rj guys are older and have more time, but tprop guys get jobs at the majors too, I'm not really in a position to answer this with anything more than speculation.
3. It's extremely common to fly more than the guarantee
4. the other guys covered the jumpseating/non rev question.