Missing from all these is a social network of "our friends and adjacent social circles". And perhaps, on top of it, a service aggregating output of all the ones you listed, so as a user, I can have (for a lack of better term) "people-first" mode of interaction. By this I mean, I want it to answer the question, "what have X been up to recently?", where X is a scope I can alter - from "all my friends" to "a particular group" to "particular friend".

I.e. what Facebook used to be, before the "great social network unbundling".