I agree; in fact I did my own checklist from the POH and then adding avionics-specific stuff.
I don't think there is (normally) a bypass on the mechanical fuel pump. Unless the mech pump is a gear pump (or some other positive displacement type) if its drive shaft should shear off then you can still push a liquid through it, and that's what I understand the electric pump would do.
However a common "selling point" of using the electric pump around tank changeovers is to pressurise the pipework and prevent the formation of bubbles. This I don't understand; the electric pump is normally in the wrong place for that.