Weighing in only backlighting, the best board I've used has been the Logitech Illuminated keyboard. It had a very clean, white light and there was no light leakage under the keys. Unfortunately in the later editions they limited the amount of keys that can be simultaneously pressed to 3, I think, which forced Logitech fans to buy the more expensive boards for gaming.
I have since tried to go back to this board I found that the keys are too stiff, and that it no longer works. This board is more sensitive to moisture than any one I've ever used in my life, and I've gone through several of these. I think it was just a humid day and I put it back in the original plastic packaging.
The poker 3 also has very nice LED features and looks. In hindsight, when I replaced all the switches I wish I replaced the white steel backplate with a black one. I dislike the look of light leakage underneath the keycaps and this would have resolved it. Stupid, stupid ,stupid.