I mostly participated in episode discussions on r/, but I feel I did benefit from other threads there, e.g. hearing news about new shows, getting linked to new official PV / posters, etc. I don't think you need to restrict it to episode discussions only, but do it as you like.

One thing I think the mods there did right was limiting random chit-chat overall by keeping them in the weekly chat threads so the sub feels mostly on-topic and not too chaotic.