Yes good idea, I've installed the apk for the leanback keyboard and it works great, also better looking than the stock mobile keyboard.
Hackers keyboard is the best that I have used. https://play.google.com/store/apps/details?id=org.pocketworkstation.pckeyboard&hl=en_GB
It's perfect for it on a large screen. Tried the Android TV keyboard but it's too small and fiddly and better suited for a tablet IMO.
Thanks @Chuck Rivers Attached is the Leanback Keyboard I nabed from XDA: http://forum.xda-developers.com/nvi...s/share-android-tv-leanback-keyboard-t2815913
Yes I agree, it's a little bit small but it looks better just like on the nexus player. If only there was a way to make it bigger...