Reality check, as requested
I don't know how much of a "reality check" this may be. The best I can do is relate to you my experience because I was about the same age and with about the same experience level as you when I tried it.
I started flying nearly twenty years ago when I was just turning 31. Learning to fly in and of itself was fulfillment of a dream. I found I really enjoyed it and kept working on ratings so I could be a better pilot. I couldn't work on ratings consistently because I worked horrible overnight shifts for a few years.
I became disenchanted and disillusioned with my business, which was radio news reporting. Then, in 1987, I started to read and hear about about a "pilot shortage." The Future Aviation Professionals of America were espousing propaganda which said forty thousand pilots would be needed over the next ten years. I say "propaganda" because, I learned later, that's what it was. I was 36 by then and had my Commercial and all ratings except multi. I had a long-time friend who was flying for a commuter and another acquaintance who had just gotten a job with Simmons. I thought, if they can do it, why can't I do it? I discussed changing careers with aviation professionals whose opinions I trusted. They said I should go for it. I finished my multi and MEI and I did.
I started by applying to commuters with my 900-some-odd hours and something like 15 of multi. This was in late '87-early '88 at the peak of that alleged "hiring boom." Plenty of spam and plenty of polite rejections, if I received any response at all. I applied at Embry-Riddle to instruct, thinking that if I instructed there it would be a decent reference. I had my four-year degree already. I got hired at Riddle, built hours, built multi, and got my ATP. I continued to spam the commuters. Primarily the same results as above; in fact, I continued to send updates to SkyWest for six years and always got the same rejection postcard.
I finally began to interview with commuters in the summer of 1990. I had five interviews from that time through the spring of '91. None of these commuters wanted me and no others were interested in me. One commuter, StatesWest, was in Phoenix, only 80 miles from me. I spammed it and dropped resumes by personally when I was in Phoenix. No response from them AT ALL.
You probably get the picture. And, to put my story into further perspective, bear in mind the times back then. Recession and a war. I was ripe but those events stopped hiring completely, just as now. Perhaps I didn't do the best interviews; I would concede that to a point. But I know of plenty of people who were hired who did less-than-perfect interviews.
My theory for my experience is threefold: (1) There never was, never has been and never will be, a pilot shortage. That was FAPA BS. Its successors continue to espouse the same nonsense. Don't believe it!! Every interview I attended was chock full of qualified pilots, including ex-military. Also, Pan Am and Eastern had folded and inserted many qualified pilots into the employment pool. Now, Emery and Midway pilots are looking. There is never a good time to get hired. Companies always have tons of resumes from qualified pilots. There are really very few jobs to be had. (2) Age discrimination. I was in my late 30s-early 40s when I was applying. Kids nearly half my age and with fewer hours than me were getting hired by commuters. (3) The economy. No airlines were hiring. I kept working via instructing. Finally, I had some bad experiences with employers during my last year in aviation, 1993. I left aviation, very bitter, and went back to school.
I feel very strongly that I was discriminated against because of age. I don't think you're too old at this point, but I suggest you keep age discrimination in mind.
One further point about age discrimination. I have seen the stories about pilots who were even in their fifties when the majors hired them. Let's examine these stories. Yes, the MAJORS hired these folks. The truth of it, guys 'n gals, is these folks were already very experienced and had been working for years for commuters, corporate, etc., with some being ex-military. I doubt that these over-thirty types were 300-hour or even 1000-hour wonders. The commuters are the usual next step after building time instructing or otherwise. How many career-changing, over-40 types do the commuters hire? I submit, a paltry few at the best.
I just give you my experiences as food for thought. Having said all that, I'd suggest you forthwith get your four-year degree because you won't amount to anything in this business without it. Finish your ratings and build multi. Instruct as much as you can. Build your time and start spamming. You need a Plan B just in case aviation doesn't work out. Maybe you might have other money available that can let you instruct full-time and let you pay for your health insurance through COBRA. I agree with other posters; don't look solely at airlines. There are other flying opportunities available that are just as good but are not as visible as airlines.
Hope all this provides you with some perspective. Good luck with your decision.
PS-I read "Fletch 717's" post with interest. It's great that he made it. But, to put perspective on his good fortune, bear in mind that luck and timing are everything in aviation. When he changed careers, the economy and airline hiring really were in flush times. You need luck. For every person who got in during those times, I'd submit there were dozens who never got past the flight instructing stage. Now, that IS a reality check.
Once again, good luck to you.