Do you need a rotating beacon if you have strobes?
As required equipment for night flight, that’s technically feasible to do as this can serve as an anti collision light, provided the aircraft still has position lights and landing lights.  However, if you’re flying a certified aircraft, unless you have an STC to deactivate the beacon, you cannot as it’s listed in the minimum equipment list for the aircraft.  You’d be opening a can of worms to do so and there really seems to be no significant advantage in doing so.