Seems like overengineering indeed. Additionally, it’s under-engineered also since Normed doesn’t store the transfer function (gamma) so you cannot use it pretending it’s just a fixed-point float!
And what sort of transfer function are you referring to?
Transfer function is the nonliner transformation used to more effectively use the limited resolution of integer values. Most typical is sRGB gamma (luminance ~ (value / 255) ^ 2.2) or Perceptual Quantization (PQ, smpte2084) for HDR videos. If you want to perform filtering in linear domain (i.e. for your color transformations to look natural) you need to linearize the signal.