I've already looked and concluded that there is very little official support amongst torrent apps for Android TV - so I'll need to side-load.
I looked at the 3 best known - uTorrent, bitTorrent, and Vuz - and they all have remote control ability, but only for controlling desktop computer from Android. No support for controlling Android from Android, or Android from browser.
I would add that I tried uTorrent and the ads were totally over the top. I don't mind paying, but seeing such obnoxious behavior in the free version makes me inclined to look elsewhere.
Flud doesn't appear to support remote control.
Transmission has a remote app for Android, but no server.
Is there anything that satisfies my requirements?
If you only want to control it while on the same Wifi, BiglyBT has a 'secret' ability to access it remotely (only from your local network). You can use any Transmission compatible remote you want, you just need to setup the remote client to connect to your TV's wifi ip address (probably 192.168.<number>.<number>), with a port of 9093, no username/pw.
Of course, I recommend BiglyBT as your remote app too, but there's plenty more good ones out there (like TransDroid, Torrnado, TorrentToise, Gear Shift, etc)
BiglyBT is on the Android TV store, but it's hard to find with the word 'torrent' being blacklisted. You can either install it to your TV from the link above when you are on a desktop computer, or you can search for 'BiglyBT' on your Android TV and it should show up.
Disclaimer: I wrote the android app for BiglyBT ^ _ ^