As a cable cord-cutter, my only means of watching TV is Hulu, which is fine. (also have an HD antenna for live events like the Super Bowl)
I don't watch a lot of sports, but love the NBA Playoffs, so in the past, I would purchase the Sling TV service for the month or so of playoffs and airplay the stream to my Apple TV. The process was not fun. Sometimes the audio would stream, but no video. Sometimes just video. Sometimes the app would crash. Weird things happened when there were commercial breaks. Hopefully, a native Apple TV app comes out before the 2016 NBA playoffs so I can avoid all that hassle. (a bonus would be if i could sign up for the service through my Apple TV, just like I do with Hulu)
Or maybe Apple will have their own streaming TV service by then....