I mostly use BAC, Extended Encyclopedia and Jaredonians Character Models + Distinct Tribes. Of all the mods in the mod forum there aren't actually a ton that are up-to-date, but BAC is, and offers plenty of gameplay improvements to play around with already. Extended Encyclopedia and JCM+DT are for extra flavor and are more minor mods.
I also use a portrait pack that I found elsewhere on the internet, and URWCharacterMenu which is pretty much a cheat mod.