CFI for (little) pay v. Paying for flying
Well, if you're working as a CFI you really don't need to pay for your own flying, so that eliminates that concern.
It all depends. Probably right at the moment it'll be hard to find work, but when hiring picks up and instructors are picked up by regionals, etc., there will be more work per instructor. New student starts will pick up as well as people start believing again that there is a pilot shortage.
Another point to consider is if you instruct at an FBO versus a 141-type school. You'll have a captive audience of students if you work at a place like FlightSafety. In addition, 141 students are usually there "for the duration," so you can count on keeping the same students or rotating among the same students for months at a time. At an FBO, you might get some who are training for the career and who will be steady customers, but you're more likely to get people who train sporadically for their Private, renters and people needing flight reviews. It's a different kind of clientele than at schools.
You can bank on maybe 30 contact hours a week or more if you have 5-10 students and enough aircraft and sims in which to train them. Expect to put in 50 hours or more a week at work to gin up your 30 hours a week of contact. Don't count on it being steady. Don't forget about weather, maintenance vagaries and student no-shows. You''ll find that you have good months and bad months.
Good luck with your plans.