the many historical values of colour
The joy of finally all agreeing on a spelling is that we don't have to guess what a word is (coulor, culler, cullour etc) or need to sound it out to guess what is meant (is 'culler' meant to be colour or collar? let me read the sentence to see which fits) but can have the word go straight from eye to comprehension. Faster understanding and communication, and ambiguity and time-wasting are removed.