I agree that the current colour scheme makes the night time hours stand out more than the daylight ones, but I would suggest perhaps a different approach - dark

I agree that the current colour scheme makes the night time hours stand out more than the daylight ones, but I would suggest perhaps a different approach - darken the background so that the daylight hours have more contrast and the night hours blend in more. This would solve the problem of your eyes being drawn to the darker spaces while still keeping the more expected display of daylight hours having light colours and night hours being darker.