Apart from too much reflectivity on the surface of the saucer (esp. near the bridge section) I think this is a fine "first go." There are always things that can be touched up, and as you say, the Ambassador's a WIP (esp. around the edge of the saucer section).
Other more qualified minds will give more specific critiques, I am sure. But, for not, tone down on the mirrored surfaces.
Damn it, Jim, it's a starship not a looking glass!
