The following is my opinions:
your right on one thing and that's the latest and greatest game. problem is EVERYONE is playing that one game. Only time "that one game" works if you stream on a platform with no one using it. Forget twitch and mixer. you may as well use dlive or something newer. At least you can show up on the top list for the next 36 hours of the drop of the game. one thing that really works is certain games that release new content every once in a while. Examples are like GTA5, Elite Dangerous, No Mans Sky, WOW. All those listed are guarenteed to get viewers flocking back to see the new content. When the GTA casino came out my numbers grew but a week or so later people were already bored of the new content. The week before new content and a week or two after are the only times i see viewership peak not only on my channel but it could be a partner streamer as well. You have to be well known in a game to have people stay no matter what you play. Don't expect a certain game to be your primary. that is where the burnout really comes to play.
You make a really good point there!
In my opinion, it's also important for all streamers to remember; the game you're playing is what gets people to click on your stream at first. But if you want your viewers to come back, let alone support you monetarily, you need to give them something more than just the gameplay. Even if you're great at the game you're playing
For me, live streaming is all about social interaction and community building. If you build a solid base, your viewers will tune in no matter what game you decide to play.
@calimeatwagon is a great example of this. No matter when you tune in, there is always something more than just the gameplay to watch. He always keeps the conversation going with the chat and it makes watching his streams so much more enjoyable.