Maybe my patience will pay off. Just noticed:
Vengeance K95 Fully-Mechanical Keyboard the K95 will be 100% mechanical, has 18 G-Keys, adjustable lighting, indeed "key by key adjustable back-lighting" ... now to wait for the release (and the price). Maybe there will be a grand sale on K90's? I see they have dispensed with the brushed silver aluminum look although they still used aluminium, it is just black "anodized" aluminium.
I'm leaning hard towards a mechanical board based on comments like 'once you've gone mechanical there is no going back'.