Finished up my test model, I ended up going with the middle silver - the slightly bluish tint. After working through the first few plates, I realized how small of an area I was working with. Nothing like space marine armor with the large surface area! So the thought of doing gold detailing throughout is nixed. Instead I put a few gold designs throughout. I think I'll do some random plates in gold too to bring out the chaotic look.
Overall, I'm pretty happy. The deckplate didn't come out as planned, next round I will start with that so I can get a good drybrush in then move on to the sand. I think I need to line in some black again to create more separation the the plates as well. The next step is to come up with the army logo / kabaal name. I think purple and green ended up being neat accent colors.
The raider will leave me a lot more space for freehand runes. I'm really looking forward to the big plates and sails.