I hope you don't mind but I've marked up one of your renders. There is clearly a bright light, on the right, below the ship casting light up. This is lighting up the secondary hull. There is also a secondary light looking down from the left casting shadows across the saucer.
If there aren't two lights, are you using a HDRI or a sky dome as well as your light?
Looking good so far. My only question/comment would be, how do they reach the dilithium housing in the reaction chamber?
This is my biggest issue with the Enterprise-E's warpcore, the housing is 2 storeys up and no way of reaching it.
Also great work on the Enterprise-D Parallels v1 bridge. I followed the link and had no idea the bridge changed so much during the run of TNG.