Although LL has stabilized the program and delivered the best two seasons in history, I don't see him fitting well with a Power 5 school. The fanbase would likely sour quickly on his style of play, and he doesn't have best the best recruiting resume.
Additionally, in his 6 years as Head Coach at UB, he is 12-20 against winning teams and 12-25 against teams rated in the top 100 (Massey Ratings). Those aren't exactly earth shattering figures, though much better than any of his predecessors.
If he does leave, he leaves the program in much better condition than he found it in, which should help the candidate pool.