Interesting, but the totally flat saucer is weird. The book says there's no rise in the center, but does it rule out a convex underside? I think it would look better with one, suggesting a shallow bowl or a boat in profile.
Alternatively, you could take "no rise in the center" to mean no distinct saucer module, just a gently convex upper hull with a recessed bridge. I think the use of the word "center" implies that. And making it totally flat just doesn't look good in profile, though it was clever of you to add some visual interest from other angles by making it concave instead.
Thanks for your feedback Christopher, I really appreciate your taking the time to write such a detailed response. Yes I agree with you about how the flat saucer does kook particularly odd. Hence why I knew that this design would be resit difficult to make look good, based on the description given in the book. Thanks also for noticing my efforts to add some details in terms of depth to the saucer section. However, I'm reluctant to give that convex underside to the saucer, as this would then interfere with the line-of-sight of the navigational deflector. I could let that little central section jut down a little bit lower, but it would have to be a very subtle alteration.