I for one don't think Peterson is in the mold of Ware, however there are difference dirrections one can go at OLB.
The first mold is your Joey Porter DeMarcus Ware type. These are generally converted down lineman that are liabilities in coverage past 7 yards but can take on tackles and not only turn run plays inside but also squeeze a tackle or pulling guard to close lanes. These guys absolutely cannot give up 100 pounds to their opposition. You'd idealy like them to weight in just under a small center's weight. I'd guess 255-265. If you drop say 20 pounds from that then he's not going to be able to turn in a 300 pound tackle. It's not just strength, it's simple physics.
This is an important distinction... If you are going to be reguarlly rushing the passer as the 4th rusher in a 3 man front, then you need to be able to control a blocker on a run play.
The second Mold is relatively unknown in football today. The closest I could guess would be Ray Lewis when he played the 3-4 (and occasionally lined up outside) or perhaps someone like Thomas Davis. Here you have guys that have SS speed and can cover down field or in the flats. The biggest thing these guys give you is an ability to account for extra recievers (RBs, H-Backs, and TEs).
A guy in this mold can play opposite of Ware, but they would absolutely not play the same role. Ware (and perhaps one of the ILBers) would be the usual 4th rusher while his opposite LB would generally line up on the strong side or across from the H-Back. He has coverage first responsibilites and is free to rush the QB when his area is free. He would also blitz in the way a corner or SS would. These guys would not be strong enough to turn in a Tackles or Guard. So he would need additional coverage inside from the near ILB. That would effectively shift all 4 Linebackers over slightly to account. However he would certainly be responsible for turning plays inside. You'd also like to play him behind more of a 2 gap DE. The 3-4 can be run with both 2 gap and 1 gap DEs. Richard Seymore for instance is a 1 gap DE, while Canty is more of a 2 Gap player. This OLB would want to be shielded from lineman and thus would be more effective behind a 2 gap player. Some people might recognize this D as more of a 3-3-1-4 instead of a 3-4-4. I'd say it's a hybrid since the Rover/OLB does have some run responsibility.
I don't know of any teams that really play with this formation, however considering the state of the league, where TE's and H-Backs are being used more as pass catchers I'd think it would be a good evolution of the 3-4. I think this is the natural adjustment to a league of single backs.
I could see the faster (Pre-Injury) Peterson in the second mold, but not in the first. He simply doesn't have the mass to turn in a Lineman. He wasn't asked to take on linemen in SF and I think he was expendable this year because of their own shift to the 3-4.
