There are a lot of Strong Safeties that could be on waivers. Donte Whitner, Chris Hope, Adam Archuleta come to mind.
At LB, NO might be a great find. Danny Clark or Simoneau, one of them will earn a MLB job. DeMeco Ryans in a non-dynasty, though it may be too late to pick him up. There were rumors of Ben Leber possibly moving to MLB for the Vikings, if so, he could become a big sleeper pickup, worth keeping an eye on how they list starters this monday.
As for DL, Minnesota has some very talented younger guys that could burst onto the scene.