CITRUS (part 2): development

I would welcome any input on what I have so far:  I use LetraSet TRIA markers so I can still add colour over top or push some lighter colour in (Mayfair paper is perfect: to a degree it let's me re-work over what I have already done). For instance, in the B&W I have I was trying to figure out about the background behind the panels.  At first I was thinking a very light neutral grey, perhaps with a hint of orange in it because the panels all have so much blue. Then I was thinking black; and that might make the lighter colours pop more - comments?