Yeah, I follow tags too, but very very few. I was talking elsewhere on Hubski recently about how following people provided the quality regarding a topic, where following tags provided immediacy regarding that same topic. As humans, we like both, and I regard tags as a kind of hack that grant us the immediacy we sometimes seek. I envision Hubksi keeping people as the primary point of entry to topics, with some version of tags (which have not been "solved") as a secondary means.

Your point about the global posts is spot on.

Also, as Hubksi scales I think that there will need to be a toggle switch where you can have your feed be comprised of the posts of people you follow and the posts they share, OR just the actual posts of people you follow and not the ones they share. It is easy to just share something, and people do it with less thought. This switch would let people reign in what makes it to their feed, keep the quality level really high (only get exactly what people you follow submit), and also let you follow more people without having their 'children threads' snowball into your feed.

But the underlying mechanisms are sound. There are all sorts of algorithmic tricks you could do to deal with the global feed problem as scale happens. I have zero doubt that multiple ones will be tried given the level of iteration currently operating.