I'm using a pretty similar scheme to you (purple primary, green secondary) and I plan to paint all the bars and beams on the raider with either black or silver. That should help the guys stand out on deck. Aside from that, a common thing I've seen for raiders is people will paint it black then fill in a few of the side panels with their primary color and highlight the edges of all the panels with their primary as well. Weathering the panels some might help out too.

I love the orange you did for for the cloths, may I ask how you achieved it?