@Jayden Neal have a look at YAPS. It has many options to set the backgound.
There are 11 different background patterns to choose from. In addition you can select different patterns for the equaliser pages
The next option, background colours offers over 200 different colours
Finally, custom gradient is infinite in that the user selects the start, middle and end colours. You can also manipultate the angle of the gradient as well as dominance of a particular area (x/y)
I'd say this is pretty cool !!