I didn't read anything in the OP that inferred a "too good" for regional attitude however this thread would probably be better served in the mil section. The mil haters are definately going to come out of the woodwork with a "will regionals hurt me" title. Lesson learned.

I drill in a mil unit that has sent LOTS of guy to the top tier legacy/majors and we have several guys in your similar situation. Its been established that getting some 121 experience will round out your resume. That said, I'm gonna approach it from a different angle.

I think the industry is at a critical point now where there just aren't enough guys willing to work for $20k a year to fly airplanes. The FAA wont let anyone hire a 250hr guy with a wet commercial so the supply of qualified new guys for regionals is very low. The regionals are shrinking, 50 seaters are going away, the majors are upgauging, Eagle is even offering a $5k signing bonus.

All that being said I think its likely that anyone who takes a job at a regional just for resume enhancement is possibly looking at a break even proposition. Yes you may be called for a major interview sooner than another mil guy without 121 experience, however by taking a job at a regional, you may actually just be delaying that same major from reclaiming the same route (and hiring new pilots to fly it) you're flying for a fraction of the cost.

There are several thousand major pilots still on furlough and lots of regionals flying jets on (former legacy) routes over 900nm. Once guys start retiring in large numbers and the majors recall and hire its only a matter of time before the regionals shift some flying back to mainline. That is unless a fresh batch of pilots walks into the regionals enabling them to maintain the current staffing levels. If they lose people, they will in turn be forced to consolidate.

One other thing to consider is that right now the OP probably has a pretty good schedule and less, but still decent cash flow as a reservist flying with quality guys/gals. That may not be the case sitting reserve at the bottom of a list without a lot of new hires coming in below you and flying with the problem child CA's that everyone else is avoiding on their bids.

Since the OP was looking for advice here's my take on your personal situation. If you have the advanced quals EP/IP/Natops etc. for your mil a/c I would probably go to work for the regional in question if the domicile you live in is one of the junior ones. If you don't have those quals I'd focus on getting them, 121 experience won't make up for area's lacking in your mil life. If you have the quals and don't have to commute you'll get some good experience and have the ability to drop lots of mil leave to avoid (most) bad deals. Plan to be gone on holidays.