Suggestion is: drop the number of engine slots to 8 or less. Freelancer cannot display more than 8 engines per 1 ship. EDIT: Or maybe 10, I'll try to find out. Anyone flying the Bounty Hunter Destroyer? How many engine trails it has?
Here's my suggestion about possible size of this ship:
Should be a little shorter than the Large Train. This would make 4500-4800 cargo capacity logical.
Also, looking at the Train model together with this one... the upper "bridge" section with the window might be made 1,2-1,5 times larger to suit the scaling.