You do know that any Android phone with an LED light has the option to make an LED light or tone specific to a personal contact? Additionally, I'm not sure what phones you used, but as of 4.3, rich notifications have been incorporated into Android, as they are now into iOS.
One, this is not as good of a solution as banners, as you quickly run out of colors and many times I can't even make out the color in bright daylight.
Two, how does the light show me if the message sent is regular communication or one that requires immediate response sent back?
Three, if I am going to add another layer of service to poll my device for notifications, I will take the banners over led light.