Let's look at what the difference in the pay is:

Say you work at regional airline "X" for 3 years as a FO, and then 8 years as a CA. I think that should be about the worst regional career that anyone should be expected to work in the next decade or so. If it is longer than that, you did something wrong.

Average Pay for that 11 years at a regional (3 FO, 8 CA):

Air Wisconsin - $62.90
SkyWest - $~62.50
Compass - $61.80
PSA - $59
Endeavor - $58
TSA - $57
ExpressJet - $57
Republic - $56
Mesa - $54

*based on similar airframes.

QOL, time on reserve, ability to make additional money (SAP, etc...), and other benefits are really the only difference between the majority of them (with maybe MESA and Republic as the exception).