In Lighting Effects, there should be a colour option for the current key colour. The colour would then be whatever colour the key happens to be when the effect is run. This way, we could, for example, have a pulsating colour gradient that is activated when the key is pressed, which transitions from the current key colour, to the new colour and back again.
Currently, the gradient colours are fixed, which can result is some jarring colour transitions depending on the colour of the key at the time the lighting effect activates.