I aiming for a sort of "color picker" selection where you can pick you own color. Perhaps even enter in the hex codes of the color you want to use. The problem is that a preview option may be more complicated than is warranted, so the drawback would be that if someone selected a color scheme that made their ad unreadable, they would waste a bump/highlight finding that out.
So I'm trying to see if this is worth implementing, and if so, exactly how much it is worth to implement. If it would cost me several hundred dollars in programming fees to implement, and it doesn't have any tangible financial return to me, then no, I can't see wasting my money.