Wind speed colours
I find the colour indicated for low wind speed (0-6mph) - blue - is too similar to the one indicated for extreme wind speed (70mph) - blue.
Some additional information to change colours.
You are right some colours are too similar in the wind range. Then I prefer a light color for a light wind, and a dense/strong/dark colour for strong winds. Fortunately with Windy you can modify the layer colour as you like !
Thanks. Changed it to how I like it now.