I've made an adjustment that is working for me so far: I've assigned Erase to the button. This lets me keep my thumb resting on the button for quicker access, and of the available options, Erase is the one I use most.
Flipping the Pen over to use the eraser might be cute and 'intuitive', but it is not nearly as quick, and requires one to position the button again after flipping it back. Maybe after a few hundred of these one can do this without fumbling, but it still would not be as quick.
Also the eraser requires more pressure, makes more noise/vibration (a tiny bit unpleasant), and feels less precise.
Now I'd like to be able to assign other actions to the eraser!
I've added to my Scribe wish list
here