I would be willing to do west coast but would probably be commuting so the farthest would probably be Minneapolis or a very commutable airport with a lot of flight options a day. I've heard the positives to both Envoy and Piedmont mainly with regards to their flow. While flow is good to have in the back pocket its also not going to be the selling point nor will be a quick upgrade catch. I had the fortune of working ground ops at an airport about a year back and talking to many pilots (all mainline) they said the quick upgrade catch isn't the way to go because 1) that can change tomorrow and 2) the mainlines won't hire you just because you have 1000 TPIC.