Home during vacation - New England

We live in the New England area and are planning to leave the house vacant for 4 weeks while we are on vacation. This is our first time leaving a house vacant in New England winter. I needed advice on things that I need to take care of to ensure the house is fine while we are away.
Here is the plan we have so far

1. Switch off main water supply
2. Switch off the gas water heater. Not sure if I need to drain it.
3. Leave the gas heating system on with temperature set to 66F. Its Wifi thermostat so can change the temp remotely if needed.
4. We have a whole house humidifier on top of the heating system; planning to switch it to summer mode
5. Electrical main will be on.
6. Planning to leave a few lights on an automatic timer.
7. Leaving 2 cars in the garage and 1 in the driveway. Will jump start them if needed when we return.

I am guessing nothing needs to be done for the septic system while we are out.

Anything else we need to take care of?

 

Sounds reasonable. If you have a neighbor who can keep an eye out for strange activities at your residence - that would be a plus. Some area police departments do vacation checks daily, if you notify them. Enjoy.

 

I would turn off the water main or main shutoff to the house. If a pipe or hose leaks or if the furnace quits having the water main off can prevent a lot of damage. I turn off our water whenever we are away for a week or more summer or winter.