I have a perfectly functioning DreamService that I want to use within my main activity along with an extra button so that the user can access settings (Android TV appears to be missing the daydream settings icon as far as I can tell).
Is there an easy way this could be done that would specifically avoid duplication of code?
Sure, just take the views you created for your service and put them in an activity instead. Make sure your views can work without a direct dependency on the service.