For Upstart and PCA; once your OmniPanel and your UPB switches are configured you will rarely need to use it.
Is the only downside to the Homeseer 3 "lite" the limitation to 5 plugins?"
Yes Homeseer 3 "lite" is limited to 5 plugins and only runs on Linux. The Zee2 is sold as a package that includes the Raspberry Pi.
That said you can configure as many scripts as you want on the Zee2.
Virtual basic scripts, python, perl, bash, et al....
Note though that the Raspberry Pi is running with 1Gb of RAM and an ARM quad core CPU. It doesn't have any moving parts and really runs on just a couple of watts of electricity.
You can purchase Homeseer Standard or Pro a la carte and it runs in Windows and Linux.
Here is my Homeseer "Lite" configuration:
Plugins running (really 6 these days)
1 - Homeseer Touch used to be a separate plugin and today it is integrated to HS3
2 - BLLAN - this is just a network devices monitoring utility. It can be configured to text or email you should a device on your network have a hiccup. Free plugin
3 - Omni Plugin talks to the OmniPanel. You can control all of your lighting via the OmniPlug with whatever controllers you have connected to your panel (Here have UPB, X10, ZWave and Zigbee). Paid plugin
4 - weatherXML - a weather plugin that connects to internet weather services and your weather if you want. There are chatty kathy pieces to it and Homeseer touch pieces. It is very popular and free.
5 - ZWave - free plugin - ZWave currently utilizes a remote POE ethernet connected RPi2 with a Z-Wave dot me GPIO card in the attic.
Amazon Echo and Google Voice is included with your main Homeseer 3 lite. (Zee2 HS3).
Also here running a few scripts that do stuff every minute. I continue to utilize 1-Wire temperature/humidity sensors.
1-wire sensors utilize two wires and each individual sensor has a sort of mac address and sites on this 1-wire network. It reports temperature and humidity from each of the sensors. The sensors are so cheap you can put one in every room of your home, hallways, bathrooms et al. (even outside).
Current application writes a delimited text file every minute and Homeseer runs a VB script that converts the text file to dynamically changing variables. Another script now running here on my Z-Wave RPi which using an SDR radio to capture NOAA weather images. The RPi2 is also running Apache2 and PHP and creates a web page which is linked to the Homeseer web pages for viewing of satellite weather images.