I think Suh would actually be a need signing for us. We don't know how Mebane is going to be when he comes back. McDaniel is a 2-down player who is on the decline. Kevin Williams is 34. Hill at this point is only going to produce on passing downs. The biggest concern though is Mebane. I think the key to whether this deal goes through is what the medical and coaching staffs think about the possibility of him returning to form.
I think Suh could actually play three positions in our base - 1-tech, 3-tech, or 5-tech. That covers a lot of bases for us depending on who we keep, who we sign, and who is injured. It also means we could move Bennett between three different positions (5-tech, 3-tech, Leo) depending on matchups.
If you think about it, we nearly won a Superbowl with McDaniel and Williams as our starting DTs. Even if we cut Mebane and McDaniel and don't re-sign Williams, replacing those two with Suh and Hill has to be considered an upgrade. We'd need to add another big body who can play 1-tech on mixed downs (unless someone on the roster can step up), but that shouldn't cost a ton.
Ideally Mebane comes back close to full strength, we sign Suh, and we cut ties with McDaniel. We also need to pick up another edge rusher - that was quite apparent when Avril went down.
Mixed downs: Bennett, Suh, Mebane, Avril
Passing downs: Avril, Bennett, Suh, Irvin
With Jordan Hill getting the most snaps among the rest of the linemen.