Your well has a static of 1'. After 2 hours of 5 GPM the pumping level is 107'. Without any irrigation, I would think that the house use will never pull the water level down to 107'. Therefore, I would set the pump at maybe 120'. To keep the pump and discharge pipe as far away from each other as possible, I would set the discharge pipe close to the bottom of the well. Also, if the pump is already set close to the bottom of the well, you should set the discharge pipe at about 120'.
If there is any flow in the aquifer, the well water will not heat up. Heat and mass balance analysis all depends on this. Some wells do not have this type of flowing aquifer and will not allow in fresh water until you displace water from the well. Then I would install a purge valve connected to a thermostat. When the well water heats up, the purge valve will dump water outside or to a sprinkler until the water temp drops. Opposite for heating conditions.
Without drawing a picture, I would put things in this order. Pump, pressure tank, pressure switch, heat pump, tee with one side to house, and other side of tee to Taco Valve, back pressure valve, and then to discharge in well at 450'. The only back flow preventer you need is the check valve on the sub pump itself.
You really need to hold about 50 PSI back pressure on this pump when discharging back to the well. Otherwise the siphon effect and no back pressure will cause the pump to go into upthrust and destroy itself. Difference in power consumption for this pump between 0 PSI discharge pressure and 50 PSI discharge is minimal.
The back pressure valve in your drawing, set at 50 PSI, will not let the tank drain below 50 PSI, so the tank will not empty to 40 and the pump will never start. Also you would only have one tank of water for the house. When the tank is empty the house would have no water. With a back pressure valve in the right place, you will have the same pressure in the house as is held by the back pressure valve. Install the back pressure valve as the last thing before the discharge pipe. Set it to 50 PSI and turn your pressure switch up to 52/72. I use a Cla-Val CRL 20-200 pressure relief valve for this purpose. It is not a cheap valve but, very accurate and reliable. I can help you with this if needed.
The flow required for the heat pump can be controlled by the pressure setting of the back pressure valve. It will also determine the house pressure. When you use water in the house, the back pressure valve will reduce the amount being dumped back down the well but, the flow through the heat pump will still be the same or slightly more as the system pressure decreases.