I am aware that colours are affected by lighting conditions, may be altered by scanners, and will look different on different devices. But the colours I am seeing baffle me.
Your 3G look appear like my 1,50G when I look at them. Your 1G appear like my 75ct. And what I am seeing in my post is comparable to what I have in my collection.
One thing is for sure, they were never printed in different colours. However, after 9 years there is a probability some variation occurs when mixing the inks. Variations may be very minor or somewhat more evident. If there would be a reason to list theses hues, the question becomes where you draw the line.
By the way, the 70ct sheet and coil stamps are examples of the variation that may occur even within a short period of time. All of these are listed as bluish violet.