I also vote "fanwanky kewl upgrade". Interesting idea, but I don't like it. It ruins the original Galaxy design.
Worst of all, it's impractical as hell.
The third nacelle location plays havoc with the whole ship. It blocks access to all the shuttlebays.
Also, the spine along the top of the stardrive section is umbilical access and support systems. That's all gone now with the nacelle sticking there. Where did all those systems go?
The BFG under the saucer evidently necessitated the removal of the captain's yacht and others things on the underside. And can the saucer still separate? Does the BFG remain and stick out? Does it separate with the saucer section?