The Raiders will likely take a safety at some point in this draft, but the timing of the pick depends on if they bring Karl Joseph back. Assuming that they do, the Raiders take a safety late in the draft with David Dowell of Michigan State.
Dowell is the opposite style of Joseph, standing at 6’1 with a long and strong frame. The thing that makes Dowell special is that he can line up all over the field, whether he stays at safety or has to step up into linebacker.
One thing about Dowell that would make him a great fit is that he plays great man coverage against tight ends, something that the Raiders have struggled with for years. Dowell is a great player all around, from coverage to tackling, but his ability to cover tight ends is the sole reason I would expect the Raiders to take a look at him.