Plenty of Pi ...
I just picked up my first Raspberry Pi 3 B. My plan is use this for the Alexia software (think Amazon Echo, Dot, or Tap). I still need to pick up a microphone but I will then be able to play with the Alexia, I also want to get my hands on the Google Home (Assistant, like the Echo). My understanding is that the Google Home is more conversational than the Echo. And, yes, I intend to tie it to my home automation.
Back to the Pi's, every time I order something from the various online stores that carry the Pi, I also order a Pi Zero. These are becoming on of my favorite Jelly bean parts (like a PIC Microchip). So far I have various Pi's and Pi like boards. Of course the Pi isn't perfect for every solution. There are times when I need a bit more horsepower, then I'll throw a full size Linux server at the problem. Or going in the other direction, I grab a PIC32 or ESP8266 (with or without the Arduino Env.). These chips are better at handling real-time processing that Linux. Sometimes the solution is to grab a combination. Right tool for the job. :-)