it seems like a good idea in principle, but what happens when something goes wrong ?
Looking at it from a WA perspective, if you add some custom code to their extension, and it doesn't work as expected, they cannot be expected to offer support.
There may well be a mechanism to do this, but I think it needs careful planning
If you do have any cool improvements though, post them, there are a number of forum members who will try them, feed back and generally give them the once over. - then who knows ?