You never know IF a major will call, so go/stay where you're willing to (or at least would rather) be for the remainder of your career.

That said, while "1000 turbine PIC" is a great box to check it seems that it's not entirely necessary in most cases. If you really don't have a preference of carrier long term I'd probably say stay and get the Captain time, and if you enjoy teaching maybe try to get some check airman time too.

There are so many other, more important variables that this advice is worth about what you're paying for it. Good luck.