The parts for my lovely deep purple Gunnar are being ordered Monday, I am 6 weeks away from bring her home

I am trying to decide how I want to accessorize her - contrast or complimentary colors. She is a very deep plum-purple metallic/pearl color. I went with a black badge rather than silver because I thought it would look better that way.

She will have riser bars with Ergon grips - so no need for bar-tape. Basically I am trying to decide what color seat bag or seat-post tail-rider sort of bag to put on her, as well as water cage color. I think that black would just fade into the background and not be noticable - which is fine - but as the bike is dark as well that might not be the best choice. Bright yellow is the opposite color on the color wheel so perhaps...

Other ideas? We know how important color is - and she IS a unique bike