The stat works best if you set up all the scheduling and features as if you have no automation. “Follow Me” and Smart recovery etc. work well all by themselves. I program pretty much from the full web interface at ecobee.com (the app is limited).
Use automation to toggle modes…this works a lot better. If ST is having platform issues, your stats should continue to do their thing. I’ve got nine Ecobee3 stats, automated in Vera, but my home setup is all ST. You’ll also have fewer issues with 3rd party automation if you only use the built-in sleep, home and away modes on the stats.
So far the best integration has been our security system. Tenants/staff toggle Ecobee3 modes when they arm, or disarm zones in the building. I also use the Ecobee temp readings to trigger HRV “Free” cooling with a few rules.
Read my post here as it will take a lot of frustration out of the Ecobee3 smart features: http://www.smarthomehub.net/forums/discussion/838/smart-home-away-and-follow-me-sensor-behaviour
Drew’s comments on “indefinite” and “nextTransition” holds apply to the fan, home/away/sleep modes, and temp changes when done via the web API. The Vera plugin is just adding this option (so you can choose) but remember that the thermostat behavior (you can program different hold types) for changes, has no effect on holds done through the web API (automation). Those tips will save you a lot of time
Smart recovery will be in effect as long as you have it set on the stat itself. You can use the data logging features at ecobee.com to check on runtime and smartrecovery etc. which takes a lot of guesswork out of the equation.