You ask hard questions. I returned to flying as a DEC at Envoy after 15 years and it absolutely can be done. I am not currently based in Phoenix but it looks to me like DECs are getting PHX while still in training and there are captains holding hard lines in May with under a year with the company. Phoenix is projected to continue to grow modestly but it's all up to AA how much flying Envoy gets in Phoenix. However you may not be as lucky as the pilots at the beginning of the DEC hiring wave.

The pay scales for Envoy posted on this website are accurate. The DEC $100k bonus is real and comes with a two year contract. To make more than that you will need to work on holidays, vacation, or days off at time and a half or become an LCA or sim instructor. Many captains in PHX sit home on reserve and fly OT on their days off.

I commute to reserve and just had a week with weather, edict times, a ground stop, a diversion, a cancellation, major maintenance delay, airport standby, lots of MELs and schedule changes for the worse. Pilots who live in base are definitely happier, but if you have flown part 121 you know things aren't always going to go your way. How you handle the challenges of the job and how happy you are is ultimately up to you.