As I experimented with adding DR to armors in the game, what I noticed is this: unlike in Fallout 1, 2 and Tactics, Fallout new Vegas applies Damage Resistance before Damage Threshold, making armors much more protective than they ought to be. As I don't have experience with core game mechanics, I would like to have a tweak mod that makes Fallout new Vegas apply DT first before applying DR, allowing weapons to deal more damage on DR-buffed enemies.
But DR is a double-edged sword: it can help heaps in terms of survival, but can weaken AP ammo significantly when a AP ammo-loaded weapon can pierce through an enemy's DT, but its DR protects it from taking too much damage. For that, a tweak that makes ammo that bypass DT also bypass DR is necessary. A preferable way to implement this would be for ammo to bypass 2 DR for every DT bypassed; for example, as AP ammo can bypass 15 DT when used, it can also bypass 30 DR, while 5mm AP ammo would be able to bypass a staggering 50 DR, in addition to bypassing 25 DT.
If anyone made those tweak mods, it would be pretty rad.