Probably start with Sweetness just because he is such a complete back and can help you in every phase and also is a ++ in the locker room.
Defense is very hard, but I go Dent probably....maybe Butkus, then Urlacher. Coaches always talk about getting dominant D players as close to the ball as possible. Impact DL are very hard to find. JJ Watt impacts the game so much when you watch a Texans game, it's almost scary.
Briggs would be a lot higher on my list than many on here. Very, very good WILL in coverage. Peanut is in the picture as well in that 2nd tier with Hampton and some others.
Sigh on Mike Brown and Tommie Harris.....this franchise could have had one of the greatest runs on defense in the history of the NFL.