Suggestions for streamers.

The very fact that there are streams dedicated to Heroes, with commentary and recordings, is a huge breakthrough. An even bigger breakthrough would be the integration of Heroes streams directly into the game (similar to Dota, for example). As for templates and the like, it's all a matter of taste, and it doesn't significantly affect the viewership rating. What usually matters are the nicknames of the opponents and the habit of hanging out in certain chat rooms.