Would love it if you could show us some samples of color that you describe in this comment…”Plus, once you’ve gone through the grey stage to the all white stage – you can start to brighten slightly again (though not the really bright colours, usually those with a high tint (lots of white added)” What colors are bright with lots of tint added?
There are some simple terminology used when describing colours.
Pure – straight out of the rainbow – bright and clear
Tint – adding white to a pure colour
Tone – adding grey to a pure colour
Shade – adding black to a pure colour
So if you compare the Tint examples with the Tone examples above, you can see there is much more brightness in the colours that have had white added as in comparison to grey added. These highly tinted colours look great on those who are very fair or whose hair has gone white and they have more translucent skin and brighter coloured eyes.