I have the first gen Shield TV (with the clunky old controller and no remote) and wanted to get a decent remote that would work with the interface and offer a keyboard, so I went through a couple of cheapo options on Amazon and finally found one that does everything right.
The first few I tried either had connection or functionality problems, mostly the back buttons didn't work. After a bit of trial and error I found this one:
https://smile.amazon.com/Favormates-Wireless-Keyboard-infrared-Raspberry/dp/B01N0SUUZS
It's got backlighting on the front and back, the android control buttons (home, menu, back) all work, the media controls all work, and the keyboard works with most apps. The microphone doesn't work (that I can figure out) and there are a lot of unused functions, and the airmouse feature is (inherently) clunky and doesn't work great.
Anyways, if you're looking for a cheap replacement remote for your Android TV setup then give this a try, $14 and it's more functional than the $50 official remote.
Bad link.