Yeah, Kodi seems to be the leading contender.
With the emby for Kodi addon
How old is that add-on and howe well does it work? I was exploring Kodi at one point in the past (never got past planning stage) and was looking to see if there was a plugin to integrate Emby but couldn't find one (there's nothing really special about it's streams, they just need to be requested the right way).
I may give that a try. I do like the idea of a unified interface versus a controller for the UI and a separate controller/webapp for Emby.