Here's what I'd like to see.
- A shift more to man defense.
- Find a way to better disguise man v. zone when playing zone.
- Free up a LB rather than a safety to cover the TE when playing teams with big TEs.
- Scheming to fix QBs exposing seams in the zone game after game after game.
- Using a spy at least once in a while if we continue to play zone against QBs who are mobile.
- Find a way to cover the RB when he comes out as a receiver.
- Get a true NT or convert to four down lineman.
- Stop relying on great talent to win games and start scheming to win games with average talent. That way, great talent can take the game over if possible, but it is not necessary (this especially helps when your talent has a season-ending injury).
That's off the top of my head.