Found this clip of Mike Pettine explaining a 3-3-5 structure he used in Green Bay that can present as a 5-down front. This could be a solution for Dallas.
The Cowboys have been better against the run in their 3-4 base but have struggled against the run out of traditional 4-down nickel fronts.
The idea isn’t to run this every down. It’s for run-heavy situations where offenses use 11 personnel to force Dallas into nickel, then attack the lighter front.
You keep 5 DBs on the field but use 3 DTs inside and 2 OLBs on the edges, with just 1 traditional inside linebacker at the second level.
One edge would feature a traditional OLB like Rashan Gary or Malachi Lawrence. On the other, you could use a versatile hybrid LB with edge experience, like Barham or Liufau. Overshown would be your lone inside linebacker behind the front.
Essentially, you’re bringing the strengths of the 5 down front in your 3-4 base into nickel without sacrificing coverage personnel.
Hopefully Pettine can help incorporate this concept into Dallas. It could give them a way to defend the run without having to play more base and risk mismatches against spread offenses.