I'd consider removing the middle engines - more specifically for the liner - and place a docking port of sorts in it's place (a loading dock/ramp for the transport and maybe a shuttle bay/docking bay for the liner, with the loading ramp underneath, in the inclined area). My reason is two-fold: having the engines in the nacelles only, also having in mind is a CTE line of ships - efficiency coming to mind, so less engines maybe. In line with this, maybe two exhausts/nacelle also for the armored transport.
Looks nice, could be an entire new line of ships in the CTE category even.
