This is definitely something we think about ( speaking with both Jetpack & Devtools hats on ) - it should be possible to remotely trigger add-on reload via the remote editor apis similar to how we're going to do external editor support for web development. I already like and recommend to people to use Wladimir's extension auto-installer for more rapid development, this is the example I'd like to start from to make it easy for people to integrate whatever their workflow is with AOM.