Make it possible for the developer to generate an APK that is not a watchface. The APK would be a stand alone Wear App. An example, The sample calculator watch face that came out with WM 3.4. The developer would have the option of compiling it to a watch face or a standard calculator app.
With all of the basic features along with the more advanced features like LUA scripting, stopwatch, animation, gps, Tasker Interaction, etc. a person could develop a Wearable APP.
I use AIDE to write Android Apps on my phone and tablet. Some of my ideas would be much easier to implement with WatchMaker than AIDE.
Thanks for your consideration,
PS: I am quite impressed with WatchMaker and all the powerful options and feature.