As someone else who has made(and continues to make) the transition from ink and graphite to the inclusion of color, I would say that your experiment so far is a soaring success!
The clock is perfect in my opinion. It grabs the eye as soon as one sees the image, and then you follow down into the shadows of the city. This gives the entire image a sense of movement into increasing depth. You have created an incredible unifying feature in the smooth low saturation blue, as it contrasts so stongly with the detailed higher saturation orange section. All in all, an incredible piece!