Fallout 3 had this MOD and it was by far one of THE mods to have, simply put it made wandering the D.C. ruins a hellacious battlefield! Being a true FPS fan this made Fallout 3 ten times better, I actually had to get a mod to slow down my XP from the onslaught of enemies you encounter from point A to B. New Vegas has been out long enough and I believe someone should get around to making this mod available. I know personally that I would more than appreciate it and many others.
I'm posting the Fallout 3 - Increased Spawn Mod ink for someone that knows anything about mods can go there and maybe tweak the old one to New Vegas. Of course try and get the authors permission first, but I'm sure they wouldn't mind
http://www.fallout3nexus.com/downloads/file.php?id=1415
Thank u