The problem I have with colour pickers is that if I want to use the same colour for a number of different elements, I have to make a note of what exact colour I used, and then it's tricky to get the same colour later. Also if I then want to change the colour, I have to go to every matching element and update.
I'd like to be able to define an intermediate layer, a "colour palette", which contains any number of named 'pots'. I would choose the colour contained by each pot using a regular colour picker, then when I'm specifying CSS colours for HTML elements, I'd have an option to use my palette rather than the colour picker. Of course I should be able to save/load palettes as well. I implemented something like this a few years ago by writing a css file in php, and defining/referencing variables for the values of various elements. Obviously implementation here would differ, but I'd think it should be possible..
The beauty of this system would be that if/when I change the colour of a pot, all the elements defined using that pot would be updated to the new colour.
Is this a feature you would consider adding? Or does it already exist? This would be a very compelling selling point of ThemeFrame for me. Even if you were to commit to develop this feature, it might be enough for me to jump in now..