I'd much rather use my own text editor over the "Startlet Javascript Editor". When trying to get new search startlets to work, it is a pain to have to keep opening up the Start++ GUI just to use a feature-less text editor. What I typically end up doing is adding in a "WScript.Echo("pausing");" somewhere in my script, save that script to a new .js file, debug and develop using that new script file, and then paste my final code back into Start++. I have to set it all up again whenever I need to test a new search query.
So, my request is that you save the user code stubs to separate files rather than SearchActions.xml.
Another important (perhaps more important) result of implementing this feature would be increased reliability. If a user changes the search startlet action to something other than "Script" and then closes out of the Start++ GUI, then all their code is lost! I did this accidentally once...
Workaround for interested users: go get Dropbox (or something similar), copy your Start++ AppData folder to your DropBox folder, make a junction in the AppData folder pointing back to the Start++ folder in your Dropbox. Now all revisions to SearchActions.xml will be saved to the cloud.