Plex REALLY has you guys beat when it comes to filtering and searching for content. Infuse requires far to many clicks and back arrows to toggle between unwatched, unplayed, listing by titles, etc.
The whole favorite icon thing is clunky and requires you to leave one filter, going back to the main menu. then cursor over to the next filter, hit select. Once you get into a favorite there are zero tools to help you locate the content you want. You have to just scroll through a long list. The library view is not much better, as you still require to many clicks to change filters.
Finally, your preventing people from searching within a favorite and it's painful. Why do we have to go all the way back to the main screen to initiate a search?
With the major improvements that Plex has made with their enhanced video and audio players, the AV quality gap between infuse and plex on appletv is rapidly dwindling. Plex's video playback is essentially indistinguishable from infuse and they recently added the ability to play TrueHD7.1 audio. They still can't handle DTS 7.1 audio (it is downmixed to 5.1), but I can "settle" for Dolby 7.1.
Infuse really needs a refresh on your GUI that focus on simply and quickly allowing the user to find content and play it, because with Plex catching up to you on AV quality, you don't have much to distinguish yourself.