Purely one ex-mil guy's opinion... don't focus too much on the $$. It's obviously important, but it can rapidly devolve to where you'd rather earn a bit less, but have a MUCH better lifestyle and schedule.

Consider the type of flying that appeals to you. We pax airline guys whine about the self-loading cargo we fly about, but deep down, it is pretty cool to interact with them, the majority being very nice and excited to be on their big trip. About every 5th leg, some kid comes up at the gate, gets starry eyed, and you feel enthusiasm again for aviation.

Do you want to fly 4 or even 5 short legs a day? Or do you prefer "dozing for dollars" with an augmented crew, flying all around the world? I found I much prefer the latter, since we are not paid when not off the gate, and doing 5 walk-arounds, getting paperwork etc etc, is uncompensated work. For reference, my record 3-day trip was 24 legs. I'll never do that again.

I wouldn't worry all that much about CA upgrade, unless it is purely the $$ you need. At AA, we have a HUGE number of mil retirees who progress to widebody FO, and then camp there until age 65. Less stress, less responsibility. Some of the most senior lines at DFW are Tokyo 777 FC, the #4 guy on the trip. You show up, do a walk-around, then sit and monitor everything, plus sleep about 5 hours each way. It's a nice gig.

As you get older (I'm 51), lifestyle and schedule become more and more important, so look for a carrier with good work rules and a good schedule. all-nighters and all-weekend flying with bad work rules gets really old, fast.

Good luck! It's a great change from the military. No debrief, you simply say goodbye after parking and go home.