One of the things I would like to change is how the jplayer skins are applied so that changing the skin only requires changing a CSS class on the container element. By using the container element class as part of the CSS selectors that should allow having multiple skins in the same css file. So we could have a css file that contains multiple jplayer skins and this could be added from style.config, or if a user wants to have leaner css they could use a custom css file with just the one skin they want. The skin name could basically be the class name that we add on the container and we can make that something that can be set from settings. Once this is integrated into mojoPortal we will definitely need to include the css by default in the skins we ship and add instructions in the sticky thread about important skin changes to explain how to update existing skins.
I'll begin the integration steps in the next few days and let you know once it is in our repository.
That would be great if you can help Kerry with the graphics work to make additional skins for jPlayer. I have no graphic skills either so it would be great if you have such skills and are willing to help.