I'm not crazy about having a single energy source, electricity. Combine that with a smart meter and a thermostat with external controllability (wifi/Bluetooth) and you have a system that outside forces can tinker with or shut off.

I'm currently on the grid and use gas, water, electricity from external suppliers. When I eventually move top of my list will be grid independence to as high a degree as possible. I could see a heat pump as part of a new build when the excavator is already on site and you've got provision for off grid power, and maybe a wood boiler.