Thank you all for voting and leaving your comments. I did read and consider all options including dark grey and red. I actually took some photos of the red trial.
However I have decided on the black. I want to add a border of triangles of the different fabrics used in the quilt and I think that will work best with black. The results of the poll as at the time of posting are shown below:
Thanks so much for taking part. I really appreciate your feedback and your encouragement.