It seems lighting has a lot to do with it too though. I mean even in First Contact when they show her jump to warp for the first time, she had a very dark color to her. Yet in the rest of the film she was bright white. In Nemesis she looked really good and not so dark in her first appearance in the film but looked darker during the battle scenes.
Personally the Nemesis Sovereign is my favorite Sovereign style. To me she just looks really sleek and majestic. Plus, warship like qualities have always been in Trek. The original Constitution was more geared for Warfare than say, the Galaxy Class for example. No families, no children, they were always on the brink of war with the Klingons. Very few luxuries.
As for Wiley's Nemesis Sov, she looks pretty spot on so far. I can't wait to see more. Once the Variants are pretty much finished I would like to see a side by side comparison of the models just to see the little differences between them.