By all means use the programmable thermostat, but, but, turning your heat off during the day is a bad plan if you have a heat pump. When you go to turn it back on it kicks in your electric emergency heat. Also those simple programmable thermostats at Lowes are not for heat pumps unless it says heat pump, heat/cool if for gas/oil/electric furnaces with a/c. The hot water heater is a good plan, we put an insulation kit on ours and did the switch on and off, saved bunches. Also, where heating and cooling is concerned change your filters regularly, dirty filters impede air flow and increase required run time.
YMMV...I don't think I have a heat pump, but for the last couple of months I would turn my AC off before I left for work and back on when I got home in the afternoon. This past month, I decided to leave it running all day because I finally took the time to program my thermostat...guess what? It cost me $29 extra NOT to turn it off and back on. I know what I'll be doing for the rest of the warm months...
A heat pump works exactly like a normal A/C in the summer, shutting off when not in use is a good plan (as you have found out). In the winter leave it running all the time so the heat strips don't kick on to help heat the house up, heatpumps can get more heat out of the warmer daytime air than the cold night air for the same energy.
For the water heater check into going natural gas, this can save a bunch of money.