Honestly, use more polys. You aren't gonna run out, since most Trek ships are fairly easy on the poly count. The rounded edges are SO important when making a ship, as they are very visible against the black backgrounds of space. So using more polygons in those instances is advisable. Where you cut the count is how you deal with transitional edges from the main parts, such as the nacelles to the pylons, pylons to engineering, engineering to neck (if applicable) and neck to saucer. Those are the ones where you clean the mesh. Spend more on the parts that will be visible against the blackness and you'll wind up with a much more enticing mesh.
