I tend to think this team has been, and continues to be, a head case and its own worst enemy for the last 10 years or so, one who doesn't truly think it can win a big game. It's painful to watch these games.
Even though I'd rather have Suh than anyone in my lifetime for a pure game changer, I'd probably go with Tommie Frazier and Christian Peter (I know, in my perfect world, we'll disregard "off the field" behavior).
Tommie's confidence and big game performance changed the course of this program in the 90s. It seemed infectious. And I could have picked from a few (including Jason), but I settled on Christian to bring real team belief and leadership, since I think he was instrumental in developing that "refuse to lose" mentality.