I would say that you should look at the company and then look at the guys/gals that you would be working with. A pure Part 91 corporate flying job can be awesome. I was about the same seniority as you at a major airline. I wouldn't go back for anything. I also work for a private corporation. These guys are a lot smarter than the typical airline manager. You may have an old guy running the show, as we do, but they will have somone in the wings who will take over. They are training him or her right now. Everytime that I go to work it is like going to a flying club to go up with a bunch of friends. I love it. With that said, I still have my seniority number just in case the smelly stuff hits the fan. Good luck.