the thing with in-video ads is if the stream isn't that important to someone they will leave rather than wait for the ad to time out. I mean lets say it was a stream to watch a movie that's new, people will wait around for the ad to time out because its worth their time. would people wait around to watch 2 guys playing a game? maybe some would but i would say a lot would just go find someone else to watch.
thats just some uneducated waffling ^ i dont have any experience, its just my thoughts
Maybe if you created a website/blog with gaming content and monetize that with ads. Putting a link to it on your streams for people to click?