at 242 wins, I'd stay at least 1 more season if you think you've got a potential postseason team coming back. they have win markers in the mix (200/250/300) for what schools want in a coach, whether they admit it or not.
On the other hand, you're not going to get a good (B- or higher) Big 6 program without NT appearances/wins. I doubt you get any of those now, at Keep Looking and coming off a 16-12, no postseason year. Maybe Rutgers.