@Alex - I think there is room for piping and conduits in this setup. It isn't that much different from my first pass at it. I've mocked up a possible hull ring structure that still has the proper gaps for window ports on the hull. Pretty much all the conduits from the nacelle pylons will go above the observation deck corridors heading to the bow.
I figure there would be Matter and Antimatter feeds going up to the nacelle tanks, a power feed to operate the nacelle, control circuits and maybe a Matter and Antimatter overflow/return feed coming back down to the engineering tanks.