I actually have some justification for this. Essentially this has to do with the manner in which I imagined the structure was built - initially it would have been uniformly covered in bricks, but over time weathering/vandalism/etc would have led to missing bricks. The effect is most dramatic on the front of the structure as this is the side exposed to the port. The sides of the house retain more bricks because they are protected by adjacent structures. (The structure on one side has yet to be built.) At any rate, this is just what I imagined. My reasoning may be entirely flawed. And I want to stress I really appreciate your well-though out constructive criticism!
Anyway, I really like the idea of replacing some tiles with dark red, Since I still need to make Bricklink purchase(s) to complete the interior I'll go ahead and order some dark red 1x2 tiles.
Thanks again for the comments and consideration you've given my MOC.
The Star Wars clone walker battle packs come with 2 or 3 (can't remember) dark red 1x2 tiles. I'm sure you could buy several of those sets, sell off the figs and have the extra pieces from the walker for practically free. Just a thought if you are into the whole buying/reselling thing.