While I don't necessarily agree with having a ship interior, since it won't actually have any real purpose in-game. I think it would be okay to have ships which you can buy with different storage levels or something. It would also be pretty cool if you could pay to customise them like paint jobs, material finishes (e.g titanium plated guns), add weaponry, maybe change the colour of the exhaust flame or whatever else, even if it's for nothing other than aesthetic value in orbit.