[jablan]

It would be nice if the colour was meaningful, i.e. if one could, at least roughly, guess the time based on the colour. Say, that the brightness would reflect time of day (brightest at noon, darkest at midnight) and the hue the time within the hour.

[Semiapies]

HSL might work better for that, though I'd cycle it around the spectrum, with the seconds value being the saturation percentage.