Here are some of the mods i used on a playthrough, they are all great-
NMC's Textures- besty high res texture pack
Project Reality- Weather and lighting mod, absolutely brilliant
EVE- improves visual effects
Imaginator- Allows you to change visual settings in game
WMX- - Weapons mods expanded
**** New Vegas- many new weapons and gameplay tweaks, works with Project Nevada, but not the equipment module
More perks
NVR strip- restores the strip
Electro City - Improves lighting at night
New Vegas Bounties1 and 2 - great quests
A world of pain- adds lots of great new areas
There are many many other great mods, but i haven't got time atm. Here is my NEw Vegas Mod manager-
I can recommend all of the mods on there, also you can go to New Vegas Nexus and choose Top 100 of all time and change the category for different types of mods.