Jed -
I don't recall colors changing for many years at a time. These machines were made at a time when people purchased one appliance as necessary usually. They didn't replace both when one failed or when they wanted to buy their first dryer. Buying decisions that are often made today in which buyers replace both because a switch on the dryer door broke, was not common back then.
Thus, pink from 1959 presumably was expected to match the pink from 1963, and etc. I haven't seen enough KM pink to know if these are lighter, but the porcelain tops exactly match the cabinets, and porcelain doesn't fade so I'd say this is what KM offered.
The biggest changes I can recall involve the Coppertone/coffee transition, and the Harvest Gold/Golden Wheat colors. Coppertone started out shaded on the cabinets and the tops and lids. By 1972 we had what you see in the '72 above - an all dark top and a shaded cabinet. This second scheme lasted a few years. Same for the Harvest Gold. By 1977 or so, they had gone to a mono-color machine all over, which matched the tops previously, so a 1978 Coffee machine was all over dark brown like the 1972's top and lid, and Golden Wheat was all over gold like the 1974's top and lid. This may apply to Avocado/New Avocado as well.
Gordon
