Well, Mike... I think you're right about the cross usefulness of the Echo with the Firestck... They really ought to be more compatible between them... But like you, I don't use many of the apps that come already installed, and I have Installed KODI as well.... nothing works with voice command with ANY remote or echo product, outside the original apps, or apps that are available through the factory channels... Once you're in KODI, voice does nothing at all. I had kind of hoped for more voice control. The One big thing that lost me was the fact you have to press and hold the Microphone button to give voice commands... No wake word type stuff. Purely manual again after playing withThe Echo for a while now.
Overall, The Firestick does a lot, with a lot of waiting time for it to find and initiate streaming of most items I want to watch... Once it's hooked up and streaming everything is OK. I installed the SpinzTV build on it and it's pretty cool as far as browsing and stuff... even some cool live TV as well... with a 20 second delay (roughly). I just watched as everyone talked up the firestick so big, until I finally got one... Google Chromecast was almost as good, and all it did was stream whatever I conjured up on the computer/tablet/phone...