I don't doubt Florida State would get interest from the Big Ten, in fact, other than Notre Dame, I'd assume Florida State & UNC are the one, two picks of the Big Ten (or SEC for that matter); and probably the only two schools who may come close to bringing in enough revenue to pay for their addition.
I don't think Clemson's attraction to either conference in nearly what Florida State's is and each year that they are remain in the good, not great range (as they were last year and much of the pre-Dabo era) they only become less attractive. Essentially Clemson needs to get out now (which is why I think they filed the lawsuit rather than let Florida State spend the money to find out what the cost will be and follow that path), because there is a real risk they could be left out of the top two if they aren't one of the first to leave.