The LeanbackLauncher is a great way to change the default skin for the Amazon Firestick:
Nvidia Shield:
https://www.youtube.com/watch?reload=9&v=H7sUvvt7Dec
This launcher provides a user interface more like that of the Nvidia Shield TV and the Mi Box.
using Downloader <> LeanbackLauncher <> LauncherHiJack
Stock Android:
You can 'make it more like Android' by easily switching to Nova Launcher etc. ...
https://www.howtogeek.com/270382/how-to-make-the-amazon-fire-tablet-more-like-stock-android/
See Fire 7 _Alexa and features
See Fire TV Stick : Notes in Drive
Reminder : Add a bit about DroidAdmin to site ?