FireStick is somewhat hackable. You can sideload Android apps onto it. For example, I got Apple Music running on it shkspr.mobi/…/yes-you-can-run-apple-music-nativel…

You don’t have to subscribe to Amazon Prime to use the other TV services. You can also install Kodi if you want to play back local media.

The FireStick will use USB power - so you can use your TV’s USB ports rather than a separate plug. It also has an Ethernet adapter - I think only the more expensive Apple devices use Ethernet.