I like it... I particularly like the detailing you've done so far.
Just a quick thought that you should feel free to ignore... might it not create a stronger link to the star clipper lineage if you flipped the Independence
, to have the cargo section on top and the nacelles below? As I recall there was a Jefferies concept that was more or less this way, and I think this would strengthen the lineage to the Hercules
(via having nacelles below) but retain the connection to the Vanguard
(by having two nacelles.)
Just a thought.