I think it is prudent to put in a manual switch between your pump and subpanel if you do not have automation or time clock to manually turn power on or off to a pump. No one should put wet hands into a subpanel to throw a circuit breaker. You have to think about the emergency issue - water is spraying due to leaking pipe or whatever and you need to shut down the pump ASAP. A switch is much easier, safer and quicker.
I have an intelliconnect. I could wire it through those relays also. Id have the intelliconnect and breaker that way.
I wasnt sure if it needed a disconnect like an AC. I can physically unplug the 120 pump of needed but didnt know if 220 needed to be that way also.