I'll revert to the original version of the gun. Stealth-wise this new one is better, but art wise I agree it is ugly as hell.
As for the hangar, from the back it looks like the deckhouse of this USS Freedom:
Slanted edges to each side, as shown here. The doors look like this Danish ship:
Two doors instead of one.
I'll see if I can use a tad brighter colours for the doors.