the 'TRC' in #7 #6 and #8 is interesting. the subtle difference in the 2 colors is nice; different from the gradients. the blue in #7 is too light though and would wash out poorly when we drop to black and white.
I understand where you are coming from and respest it. If you a concerned about the black and white or grayscale, I can suply you with a revised version in grayscale without any loss of detal.
Thank you for your Feedback, I will take it on board and go with it,