Any but you can't name them?
For safeties I would take literally any proven free agent over Heath (Tre Boston, Earl Thomas, Collins, Amos, Joyner, Clinton-Dix, Mathieu). Even older vets like Mike Mitchell would wipe for the floor with Heath and give you a nice 2 or 3 window to draft someone younger.
DT I would like Richardson or Henry Anderson if they go cheaper on safety (both would be huge upgrades but will command decent salaries). If they go all in on safety then I would eyeball Wilkerson, Malcom Brown and Danny Shelton (all 3 would be significant upgrades).
Christian Covington is for sure the biggest upside due to his age and consistency, I would 100% offer him a deal and make him a starter (he's the type of guy will mcclay likes, upside and immediate value).
You could have enough to sign two of the DT's listed and still have enough to get a run defender upgrade like Hankins or Margus Hunt (both won't command much)
Who do you like on the list ?