Re. removing pump and using water mains pressure, just be aware that these machines when plumbed fill the water tank with the incoming water. There is a solenoid that opens to let water into the tank when the tank water level gets too low.
So to remove the pump would require at a minimum a bit of internal re-plumbing to connect incoming water to the supply for the group when the lever is cocked. What else might be involved I can’t comment.
Not that I really understand the obsession with removing the pump anyway…..