I think that Wolf brought 2 things that no one else did last year. First, strong and quick interior players often killed us. Wolf was able to stop them better than others by a combination of height and ability to handle some bulk. TO would get blown by and not be able to recover and other guys were not strong or tall enough to really stop them. Giff was doing better at the end of the year.
Secondly, Wolf had the awareness and stones to try and make plays. He made some big baskets when we desperately needed someone else who could score. TO would often get stuffed and other guys would often not look to shoot anything more than a putback.
Having said that, perhaps Nolan, Facey, and Brimah can develop and contribute in other ways. I still wonder how we will defend those 6'7" and 230 lb. PF's who killed us last year. It's funny how The Boneyard has completely written off Tyler O when he still might be odds on favorite to start the year at center. I do not suggest he should, just that he could. I would rather see the best of Nolan, Facey, and Brimah get the nod, but the coaches may not go that direction with Tyler a senior.