Looking sweet! I dig everything except the little fins coming off the nacelle struts, and even those are justified by way of visually balancing that upward curve.
You also seem to be losing some deflector detail when it glows blue, which is still visible when it doesn't. I almost prefer it with no glow. Maybe tone it down a notch?
Ever consider implying rooms behind those windows? More like Voyager and less like the Enterprise D? I'm a big fan of using photographs of office building windows at night as ambient maps, with the flat white you have now as a spec map gloss, and inverted for the bumpmap to imply an indentation. It could give you another +1 to realism.
Don't know how finished this version is though, so maybe something to think about for your next project?
I'm also quite jealous of you lack of visible poly corners, especially up close. Is it all NURBS? Can we get a look at the current wireframe?
Maybe add variations in hull panel spectacularity, like the interference paint of the TOS refit?
But maybe now I'm just pushing my personal sense of aesthetic on you.
There have been so many Treks, and so many design elements to either cling on to (yuk yuk) or abandon...