Last summer we had a new heat/ac installed, which they installed a builder grade thermostat. It's worked great, but since the kids moved out, I wanted one that would let me schedule away times to not have it run as much when no one is home.
I've also been working on some home automation stuff lately and one thing I've been wanting to do is to somehow turn on our furnace fan to circulate air when our pellet stove is running. So I picked up a new thermostat that works with my home automation hub. The new thermostat can be turned on remotely, so the automation hub can get temperatures from sensors in other rooms, and either run just the fan to circulate air to balance things out or kick heat/ac on to keep the house consistent.
One other great feature was that it will kick over from heat/ac automatically depending on which direction the temperature is moving. Last night was our first real cold spell of the season and I noticed the smell of the dust burning off the heat exchange this morning, so seems to be working since it was running ac last night.
The thermostat: https://www.amazon.com/gp/product/B00SYPSIRU
The home automation hub: https://www.smartthings.com/uses/monitoring-security
The one thing I like about the smartthings automation hub is the ability to create my own smart-apps and device handlers. They have a good community of users and their development API is open for those that want to do custom handlers for devices that weren't necessarily developed for the hub. The user community is also good about posting their custom devices for you to add to yours and helping make new ones work.
I know Carol has some plans for doing some arduino development for running a few items around the new house, might be worth a look to see if some of the devices will fit your needs. I can also double has home monitoring and security by adding motion and door sensors.