Go wherever it is that affords you what you deem most important in YOUR life....Whether it's basing, commute, equipment, reserve life etc etc...
I spent time at 2 regionals, did the 91/135, did the largest fractional, did some King Air work, and now am at a Legacy.. furloughed twice, a few bankruptcy contracts, commuted a short distance for a few years, have lived in base, have waited years and years for an upgrade etc etc...
Now that I made it to where I want to be (Long Haul International etc) the 10 years I spent trying to get here seem worth it. I hardly remember the really bad stuff to get here, and often relish the time I spent at a regional.. At times it was really fun and since I was a newbie then I learned a great deal. Did some cool flying in crap weather 4-5 legs a day. (Luckily I worked for a "better" regional with good hotels and a better contract, ya know, the one that got whipsawed out of business 2 years ago)
It is what it is, go in knowing it will get better depending on what moves you make to better your career.. (In my case the regionals were stagnating so I bailed to do some corporate flying, it worked out in the end for me)..
The guys who truly think they are soooooo awesome that they will spend 2 years in the right seat, 2 years in the left seat and be at a Legacy are the guys who are bitter.
Be humble in the right seat, and go there knowing
A) You do not know everything, and
B) the guy to your left has been there and done that.
C) No one cares what you did in a 402 while hauling a few bank checks across state lines (just an example from a guy I flew with in the past)
It'll allow you to learn from experience rather than be annoyed at every little thing each Captain does differently. If you can upgrade within 4-5 years consider yourself fairly lucky.....
If you keep flying, try not to be too disgruntled (everyone is allowed to complain a little bit), and keep your eye on the prize (whatever it may be for YOU), you'll make it out in the end.
Good luck
PS... take any advice on here with a serious grain of salt.... Pilots are notorious for thinking they are always right..
Some of the most sage advice you'll ever receive.