What's preventing you for from casting about your niche interests in channels?

How can we make it easier / more likely that you would do it

If we changed channels to "narrowcasting"

 i.e. only people who follow the channel will see it in a feed vs. today where all of your followers see all of your casts regardless of channel

1. I would want this for most channels
2. I would want this for some channels
3. I would  want this for only a couple of channels

4. I would want this for no channels, but I'd like the ability to mute any given channel.