Here is how my Audya is set up.

1)First thing I did was to backup the User Styles Folder to my PC.
2)Then deleted everything from the individual folders on the Audya.
3)Next I loaded all the styles I use into the appropriate folders in the USER styles (quite a few less than the factory styles)
4) With the introduction of new styles I temporarily put them all into one of the little used folders (you could use "Unplugged" for instance) and then went through them making a note of all the ones I liked.
5) From the "unplugged" folder I moved all the files I liked into the correct folders and deleted the ones I don't need.
6) This is ongoing but I am changing the MIDI styles to Audio from STYLE VIEW and then deleting the MIDI version.

It means quite a bit of plugging and Unplugging of the computer, but when finished my USER styles will be filled with only stuff that I want to use. (which I will back up of course)