Fascinating! This is much more interesting to me as an artist and a fan than 80% of what I typically see.
I think you could go bigger or sharper with the saucer and its edge.
The bottom I think you want to be careful not to make too blade-like. This ship isn't gunmetal gray, is it? With corrugated razor edges??
I think you should strive for more elegant and sculpted if you create more refined versions...more curves under the saucer/dorsal, and more delicate nacelle ring. There's something very scary about being killed by something absurdly beautiful.
If the overall idea is in detail this would be an organic ship (a living structure being more futuristic) I'm curious what the next step is after organic.
The D looks organic in shape. At most, I could imagine it being grown, but it's still lifeless. Say the G is actually organic and looks somewhere between the D and this. What's the future after organic? Say this is the E-L. Is the hull a transparent crystal? Is it an animate living changeling-like structure? Is it all force-fields and energy?
