This mod’s title refers to the new ships only, but it actually includes so much more -- like stations, races, technologies, planets. And all this is supported by a new AI. The overall number of features is striking, and there is a whole website dedicated to explaining how everything works in the NSC mod.
One thing that you should definitely consider in this mod is to build yourself an Empire Flagship. It takes three in-game years to build, but the rewards and bonuses you will get are simply mind-blowing.