Well, I use jsawyer.esp, a few other mods that increase the game difficulty, and then get a perk-every-level mod to even it out in New Vegas. But jswayer.esp is my favorite major balance tweak mod for New Vegas - my problem with most other mods is that they do too much, you know? I really don't like to drastically change the vanilla experience, most of the mods I pick up are to tighten it up and increase the difficulty in a more natural way - that's exactly what jsawyer.esp does perfectly.
It would be interesting to see if developers from Bethesda release any unofficial mods, especially now with mods on consoles. They've released official ones in the past, like Fall of the Space Core for Skyrim (which never got a Volume 2... unless, oh gawd, "Fall of the Space Core, Volume Two" is the official Fallout 4 mod) and the really meh free plugins they put out for Morrowind. There was one real-time carriages mod a dev put out for Skyrim, but it was delivered in an unfinished state since the dev was spending too much time, you know, working on actual games.