You would be fine with Project Nevada.
Project Nevada is honestly a 2nd/3rd time through mod, imo.
It changes a shitton, but even if you take the 'no-change' version, it messes with a lot of the stuff in the base-game in terms.
Most of it is arguably for the better, or at least, more immersive, but I don't know if I'd call it necessary, at least if you already have the sprint mod.
Nevada Skies can be fun, as long as you either don't mind rad-sandstorms or turn them off. (You'll also probably need to get one of the brighter nights .esp mods unless you like pitch black nights lol.)
Personally I like weapon mods expanded, but that has some potential balancing issues, especially in de-modding some of the unique weapons, which can be hard to purchase if you were looking forward to finding them.
I extracted the contents of the 4GB mod to a separate folder and not the main game folder. Is this the problem?
IIRC you have to move at least some of the contents of the 4gb mod to a specific sub-location within the main Fallout NV directory.
edit: Though I may be thinking of the script extender.