Quote from Lewshizz
So my larger ships can theoretically be a ship from a series (i.e. A Ship from a movie like a Star Trek and or I heard someone say this earlier Halo)? Also would this mod alter world height because of course many ships are too large to fit in the current height of the world.
Yes, absolutely. You can build ships however you want, as long as you can attach engines and life support and stuff. Check out the ships section of our forum; a number of people have built recreations of famous ships. I'm personally a fan of Imperial warships and I intend to fly them.
The Minecraft world as you know it has little to do with Futurecraft. You will be on a planet. If you go up, you will be in space, because that is what happens when you are on a planet and then you go up. World height won't be a thing.