I imagine most of this is pretty challenging, at least from a user-interface perspective. In the same vein though, I'd love to be abel to copy a whole script, not just one line at a time-- Often I make scripts that are duplicated to different triggers with slight adjustments between them.
The idea of separate patterns & scripts (as opposed to the current linked setup) was originally tossed around. It ended up being a UX nightmare though, so never got passed design stage. It would be powerful to have separate access to them, but the way patterns are often used as simple variable lookups / working data might make the patterns so incompatible as to be useless. I guess it would work if you were very strict about how you entered / modified data in the patterns so your scripts would at least continue to work when changing between patterns.