You apparently are 100% absolutely certain that the doppler effect is causing the Red shift. I'm not.
Can you explain why the red shifts appear quantized? Do you assume that the differences in redshift among apparently associated items is always an illusion?
Spectroscopy is not my specialty, but I know this much. Spectral bands in light are affected by the chemistry in the source of the light. Chemistry and physics at the quantum level have quantized signatures. So when we collect data from astronomical observations using spectroscopy, the observations are used to estimate a great number of things including for example, the composition of the star or source of light (burning hydrogen vs helium, vs other gases). Being able to correlate each quantized color band to its chemical source allows us to very accurately measure the Doppler shift on that band.
As to the rest of the mysteries of the universe, I hope you don’t expect FReepers to go off and research all your many questions.
I enjoy a quick discussion on a topic, but I am not going back to school to satisfy everyone else’s curiosities.