Viewer Achievements and Reward Redemption
Twitch has some achievements for streaming but could we have some for viewers?
There could be achievements such as:
Legendary Lurker - obtained by watching (X) stream for 30 min without typing, once per stream
Chatty Champ (look I like alliteration) - Obtained by chatting (X) number of times per stream
Emote Enthusiast - Similar to the one above, but for using the streamer's emote
It could work similarly to channel points and use viewer achievements to unlock badges related to the achievement (I was inspired by the new mute/eye badges) or redeem bonuses, such as extra channel points for X number of minutes once per stream.
Streamers should be able to toggle, I know some people prefer to choose their engagements and this might be one they would opt out of. I'd love to see the viewer get more rewards for hanging out and supporting their favorite streamer!

-
Aremok commented
If they achieve all three in one sitting they earn 'The Twitch Trifecta'