As a regional airline pilot, I'll venture forth some answers to your questions. First a little background: I started Skywest as an FO in the Brasilia based in Sacramento, CA while living just north of Burbank. I commuted for two months until we moved to Portland where I was based for almost two years. I transitioned to the jet and we moved to Salt Lake City where I've since upgraded to RJ captain. I'm married and we just had our second child six weeks ago.
Time away from home: In the Brasilia, there are 1,2,3, and 4 day trips. Most schedules have you working any combination of the above to give you four working days a week. In the jet in SLC there are mostly 4-day trips with 3 days off a week. There are some 3-day, 2-day, and locals. MOST schedules have about 13-16 days off in the month clumped in 2-4 day clusters. Reservists get 10-11 days off.
I started commuting to reserve. YUCK. I was fortunate to have good friends to stay with in Sacramento while I sat by the phone. Once we moved to Portland, being on reserve was great because I was home all the time. Once I got off reserve I flew mostly back-to-back 2-day trips. It was great too! I transitioned to the jet as a pretty senior FO so I got some REAL good schedules. Mostly 3-day trips with 4 days off inbetween. Now I'm a real junior captain on reserve. I live close to SLC so it's awesome being on reserve at home. I fly about ten of my twenty days on.
Impact on my wife: She was nervous when I first got the airline job. She'd heard the typical stories about airline pilots having affairs and broken marriages. It took her a few months to get over that. She still doesn't like me away much, especially with the kids, but it's not nervousness- she just likes me being around! My kids are still too young to really miss me, although my son is starting to ask "where's daddy?" in the mornings.
As a new-hire, I would strongly suggest moving to your domicile- especially if you're going to be on reserve. The company does not pay for any lodging in your domicile so you'd have to find a crash-pad or have your own place there at your domicile. A car there would be smart also. These just make your costs go up when you're making very little. You'll only have 2-3 days off a week and the longer your commute, the less time you'll have at home.
I know many who commute and love it. The benefits of living where they want outweigh the time commuting for them- especially if there is other family around. Support for the homefront while you're away is very important. Personally, I enjoy just hopping in my car to go to work not stressing over flights being full or getting bumped out of the jumpseat. My biggest concern is which CD I want to listen to on the way to the airport!
Regional airline flying is great, but I think the majors can offer more. My goal is to get on with a major as soon as they start hiring again. They offer more money for more time off.
I am very satisfied with the career path I've chosen. While I do have to go away on trips, I find that overall I'm home more than my friends who have 8-5 office jobs. While my seniority affords me more money and time off, they're lumped with more responsibility and time at the office.
Anyways, I've rambled on too much! Hope this helps and good luck on your path to the flight deck!