I think just to round off Star Trek ships, build one Romulan Warbird class and one Cardasian Galor Class Cruiser. After that probably whatever comes to mind as I get inspired. You know we never would have been able to build ships this good in GalCiv2. The shipyard is so well rounded its just going to get better and better with the updates.
I predict GalCiv III will be Game of the Year 2015-2016 because of people like us testing it. It just keeps getting better.