I know exactly how you feel ... I also have a frozen ATPL with a recent MCC, all completed modular !
I am currently 21 years old with 400 hours and have just started the FIC ! I to had the frustrating feeling of not knowing what to do next ... not prepared to do a type rating unless a job was almost garunteed !
So the FIC is how im going to build my experience and hours once complete. I can't see many other options available apart from joining an airline in ops, and getting to know the right people ???
Age is on our side, and if i do have to instruct for 4 years will only be 25 ... so whilst as much as i expect to enjoy instructing - i still want to fly commercially as do most other instructors !
Good luck