Mixer should display the number of actual people in chat next to the viewer count number. This number should be taken into consideration when displaying the top Mixer streamers. This would help eliminate situations where current viewer counts are being manipulated by embedding a stream into a popular website / wiki / etc (or other means). This would also help reward the smaller viewer count streamers that have built a solid active community that participates in chat. I am also sure that sponsors would love to see chat user counts as it helps them have a better idea on how many real people are seeing their product being used on stream.
I'm on board with this idea!
Sounds like a good idea.