Warrior One. I always paint on a surface that is not white. This little painting is a good example of that. See around the clouds - that orangey color showing through? - that is the color of the panel and I just love that effect.
Orange is my go -to ground color for most paintings - a habit picked up in art school that has never left. Many artists switch the background color to a warm or cool color depending on the overall tone of the final painting. Ex - cool blue background with a warm toned painting.
Not me - I'm happy with bright orange :) in most cases - the Sofia painting was painted on a very pale umber because a lightness effect was the point...
try it! experiment with different colored backgrounds - you just might like the results.