There's more flying jobs out there besides regionals and charter. You can get a pretty "sure" job flying pt135 passengers or cargo after CFIing. You don't even have to CFI, I know guys who flew skydivers, towed banners, did aerial survey. You have to look a little harder for these jobs, but they can offer better QOL and starting pay than the regionals.

I'd recommend you look into the 135 forum here and look at job listings to get an idea of what types of jobs are available, their pros and cons how they may affect your career progression.

No one but you knows what type of career you want to have, but to think regionals are your only option after CFIing is like thinking McIntosh is the only apple you can get. There are many jobs out there that can lead to a rewarding and enjoyable career, and there is definitely no shortage of information on this site and other places.