Firstly, it would be really handy if you could externalise the background colours used in Confluence. We use a light grey as our page background colour, which means that I have to edit the site-css.vm file to change the background colour and the appropriate contrasting colours (darker grey, etc.)

Secondly, it would be great if the background (and other) colours were defined in a consistent way. Some are listed as white others as #FFFFFF. Some are called grey or lightgrey, others are hex codes, which makes it tricky to do a global search and replace. Externalising these should also ensure greater consistency.

And thirdly, the background colour is also hard coded into different sections of code, apart from the site-css.vm file, making it very tricky to track down all the instances that specify the background colour.