Go to a company you plan on staying at. Stay there and get seniority. Even with your fewer hrs a month you need to take into account the two months of interviewing, getting hired, trained and then hitting the ground. Then you'll sit reserve and may not get as much flying as you are wanting. Some places might have training contracts where you'll be locked in for a year or two. Think about where you want to be and why Mesa is on the bottom as you stated. Then think about whether you want to be a supporter of those kinds of work environments. Joining them is fueling their success of running their operations the way they do.

Get your hours working either at your current job or as a CFI. A CFI shouldn't cost you 4-6k. It's only commercial maneuvers in the right seat. I did everything on mine in under 2k. The rest is bookwork and you can do all of that on your own.

There is also the consideration of the initial expenses with being hired. Unless you stay where you are you'll spend a little money no matter which route. My suggestion is to pick a company you want to work at then continue till you get there. Don't go somewhere with full knowledge of jumping ship.