Another thing that really helps with keeping the colour balance looking nice is to blend the Ha with the red channel 70:30 and using that as R, instead of using Ha as a L channel.
The 3rd option is to layer the Ha in as a L layer, then copy the colour layer, paste it into the image again, and make that layer reside between the Ha and the colour data, set its blend mode to multiply and adjust the opacity to taste. at 100% it will make the image pretty ugly usually.. I find anywhere between 30% and 70% does the trick depending on the image...
Ps - Your Cone image is looking really nice.. If I recall correctly it was a little garish when you first posted it!
