I've been at a SkyWest for six years and don't regret it. Sure pay was low to start off with, but my wife and I were young with no kids. Now we've got three and are doing fine.
To answer your questions:
Why should I or shouldn't I go to a regional carrier?
You
should not because the first year pay is horrible. It would be very tough with a family.
You
should because it's great experience and you'll accumulate flight time quickly 600-1000 hours a year.
You
should not if you are not willing to move. Commuting for a regional, while it can be done, sucks with a family wanting you home for more than one or two days a week.
You
should because you can upgrade in 2-4 years and get valuable jet PIC time.
Are any of them upgrading new guys before the next decade?
I don't know the exact upgrade times and with the latest Delta and NW Chap. 11 fallout and the the USAir/America West merger, things seem to be changing daily with the regionals. Typically Skywest, ASA, AirWisconsin, Mesa, CHQ, Trans States, ExpressJet have all had upgrades in the 2-4 year timeframe. Eagle and Horizon have been notorious for long upgrades, 4-7 years. Many of the smaller Beech 1900 operators have upgrades less than a year.
Any in particular that I should set my sights on or avoid, and why?
Any of the above with the exception of GoJet would be great options, and I'll let someone else go into that ball of wax. It all depends on where you want to live. Most regionals operate the same and have similar work rules, pay and schedules. Some have training contracts that you have to watch out for. Example would be Great Lakes in Denver- I think it's 15 months- if you leave before that you have to shell out like $7000. ouch!
Am I better off building Multi PIC for a while (I have "lots" of M/E SIC, but less than 10hrs. PIC)?
With so many of us with jet PIC on the market for the majors, it would be a tough jump from Piston PIC to a major. Many are looking for turbine PIC and even have a requirement for 750-1000. It would be good if you could find a charter operation that's got the potential to move into a jet PIC spot.
If I fly freight too long, will it become more difficult to cross over to something like a corp or frax operation - or even a major?
I never flew cargo, so I can't answer that.
Any other suggestions?
Despite the downturn in the industry, you're still in a good position. With the likes of Southwest, Frontier, AirTran and JetBlue, there are still good career pilot jobs to be hadat the airlines. Sure you may not get to that ultimate 747 international gig flying 10 days a month for $250K, but you'll have a great job that pays a decent wage.