Yeah, I can see how just using the smart home skill is limiting. ^_^
Security:
Alexa, tell homeseer to set the security mode to arm away.
or
Alexa, turn on arm away.
Thermostats:
Alexa, tell homeseer to set the living room heat to 69 degrees.
or
Alexa, set the living room heat to 69 degrees.
In all seriousness though, I think it is good that Homeseer offers this and it is a great way for people with that product to get up and running with Alexa. It's just my personal preference that I don't like ANY of the "tell XYZ to ..." methods on Alexa.
Surprisingly, I've not been as limited with the basic smart home skill on/off and temperature/level commands as I thought I would be. I activate OPII buttons/macros with "Turn On" commands as well as I control my Denon amp source selection with On/Off commands. I do things like "Alexa, turn on Tivo" which switches the Denon Amp on and changes to the Tivo input (or DVD, Playstation, Apple TV, etc.). I also use the the dimming commands to control volume on the Denon by saying "Alexa, set inside amp to 55". I had to role my own to do this, so yeah, having Homeseer do these things out of the box is a good thing.