I ran with most of the mods included as recommended.
Courier's Stash Pre-Order Pack Selector
NPCs Travel
STUN (though I never used it)
Project Ultimatum (ditto, when everything's trying to kill you)
Digital Nightmare (Great music mod for a creepier feel)
Better New Vegas (more ruined look to cities)
Apocalyptic Mojave (same as above, for other external areas)
Wasteland Defense (sort of hard to use due to lack of caps)
Real Time Settler (sort of hard to use due to lack of trees...)
Combined Weapons (for when I didn't feel like shooting things, or ran out of ammo)
Flashlight NVSE (good for the darker everything, if you can find one)
Understone (though I haven't found it yet)
Private Property Expired (fixes some interior objects being marked as "owned" and preventing use)
Tunneler Misbehavin' (because fuck Tunnelers)
Project Nevada (for sprint, bullet time, and other nice things.
MTUI (because the default text resolution for PC is way too big)
The Mod Configuration Menu (lets you configure a few things)
Unified HUD Project (ties the HUD mods together)
One HUD (lets you add things for the hardcore needs, which is mainly what I use it for, also lets you reposition HUD elements)
Tutorial Killer (because seeing the same messages after you've been through character creation a few times is boring)
Delay DLC Combined (Ditto above, prevents instant quests to DLC areas)
All in all, a very light mod list for me. I haven't gotten very far, but the thing that's most off-putting about it isn't the difficulty, it's more the lack of direction. For a plague bombed hellhole, there sure are a lot of people left over to kill. The advancement is a bit slow as well, it feels like it takes forever to advance from level to level, likely because there aren't any quests.
It would be a great survival game if other players were involved (a la Rust) but as is, it's basically just move from area to area, kill things, get marginally stronger, hope you don't run out of ammo, rinse repeat. At least, once you get out of the "running for your life from Tunnelers" phase of the game.
There's also the bugs I encounter from time to time, like the invulnerable children in the NCR Correctional Facility ruins, randomly losing/gaining karma from various acts, and getting messages that [person] has died, when killing the now generically named NPC that replaces them.
I did get exceedingly lucky on an enemy dropping a Marksman Carbine (semi auto rifle that tends to instantly kill any human enemies in a single shot, has a zoom function, and requires 100 Guns skill to get the most out of it). It takes 5.56 ammo, which is somewhat plentiful. I also broke down a bunch of other ammo and made more, so I had around 50 rounds of 5.56 to play with. Later, I found a Sniper Rifle (and a few more in the aforementioned NCR Correctional Facility) with enough ammo to comfortably sneak headshot most enemies.