Hi @joel_eggenhuize, yes you can! I’d recommend to use good temp/motion sensors with refresh capabilities such as the Iris Motion/Temp sensors (2nd gen) or the SmartSense sensors.
Please note that I have a paid smartapp that brings even more features. EcobeeSetZoneWithSchedule allows you to choose the calculation method (avg, min, max, median, and heat_min/cool_max) to apply for the temps collected at your remote sensors.
Also, you can define different zones in your home in order to take into account only the right remote sensors at a given time of the day (ex. during the day, only the ground floor excluding the upper bedrooms;in the evenings, the other way around, etc).
My smartapps only work with Myecobee Device available at my store.
http://www.ecomatiqhomes.com/store
For more details on MyEcobee device, it’s capabilities and its benefits over any other ST connected thermostats, refer to this thread:
Regards