I don't think the point of livestreaming is to grow your channel... but I personally think the whole idea of "growing a channel" is redundent, and instead you should be focusing on growing a community, and a library of content that people want to watch (that will naturally grow your channel)
Livestream because you want to get mroe one on one with your community. If you're only livestreaming to grow, people will see through that and you'll rarely get anyone to watch. Stream because you want to share something of value with your audience (a topic of discussion etc) and you can start building a more dedicated relationship with your audience.
I think weekly would be the maximum, but you could also stream every other week, or even once a month. You won't get as many views on a livestream as you will from a regular video typically.
