It is a neat idea, only thing I would suggest is that I might not invite float to the party.
AnalogRead returns 10 bits (0-1023)
You might want to look at the individual bits and assign them to colors directly
say 1 bits for intensity, 3 bits per color
analog read returns 1023 = 1111111111 in binary
intensity, R, G, B
1 , 111, 111, 111
multiply R, G, B by 18 and if intensity is set add 128 to each.
Edit: while this isn't technically hue, it will give you access to more color combinations and intensities than hue alone would.