Yes, in Bounce we use _HILDON_NON_COMPOSITED_WINDOW. This should bring clear&swap performance up to at least 80 fps.

There is no need to resort to any trickery like sleeping or flushing to gain performance, they will only make things slower. The fewer you bother EGL/GLES the better.

Notice also that the rendering is asynchronous if you don't do anything that forces synchronization. This means that the application doesn't have to wait rendering to complete before starting the next one which allows CPU and GPU to work concurrently.