I feel these things are individual preference and you should use them as how you want to see your Aro. Some people love to view in natural colors, some with enhanced looks etc.
Reg the background, its believed that white background helps in developing the shine and crossing, next option to white is blue. Black background helps to deepen the golden color.
All these are based on experience sharing by many over internet forums, I am currently having a blue background and warm white lights for a year plus, and I am quite happy with it.