If they're your best players (and they are right now), then you do. Good coaches design their schemes to highlight the best players. You can run a sound one-gap 3-4 defense--ask Wade Phillips. Every defensive scheme is designed around 2 or 3 players' strengths.
The issue right now is that our scheme isn't designed to highlight anyone's strengths except maybe Daryl Washington's. There's no reason to draft a cornerback 5th overall and then put him into a scheme where you don't require elite cornerback play.
That's pretty much it in a nutshell.
The DC has got to have the creativity and the stones to say this is just stupid, this is what I have to work with, what defense can I conjure up that uses these pieces in the best possible way?
Instead they're just playing whatever particular schemes they're in love with hoping the players will grow into it.
We're not in Pittsburg, we have no Lber's worth anything, well one is, other than that you had best design something that plays to our strength in our D line and one CB is a shutdown corner, go to a 4-3 with bump and run coverage, get your pressure from your D linemen.