Now that we have umpteen project templates, I think it makes sense to have the ability to organize them better than a SINGLE alpha listing of ALL of them.
 
Being able to arbitrarily organize project templates into sub directories and have the Start screen and new project dialogs both support folder navigation would be VERY helpful.
 
The template save dialog would need to support this as well ... I think it already does.
 
Oddly enough, track templates already support sub directories.
 
While we're at it, we might as well have favorites and pinning for project templates too!