AbigailII: Anyway, so that deals with your objection number 1.
As to your objection number 2, you have the same problem if you upload your own stylesheet - it may grow out of date as Fencer changes things.

This said, I'd also like to have the choice of uploading my own stylesheets and use ones uploaded by others (or at least check them out). I'm not trying to argue against this particular idea at all was just trying to offer some alternatives while this option isn't made available.