That's one of the biggest possible negatives in my mind too. However, there are other ways to get people fresh content and opinions. But, we might have to make an extra effort at it now.I do, however, wonder if it will limit the heterogeneity of opinions.
I don't think that's really an issue you should be addressing. You've already fundamentally shifted the paradigm from a tag-centric browsing to a person-centric browsing. Heterogeneity of opinion comes with following people with a variety of opinions. And the freedom to curate your own content according to your own ideas about what/who is appropriate for you is much more powerful and welcome than the heavy-handed "heterogeneity is important"
Don't get me wrong. I'm not talking about pushing content with the intent to mix things up. I just think we can do things that can take a person's sphere into account when suggesting content in the future. For example, today we removed the ability to have some global posts filter into your feed. (With the new global posts, it became much less useful) However, I can imagine replacing that function with a better optional feed, where you can toggle just how far out from your following/sharing circle the posts come from.
feature requests are good signs! once you've crossed the threshold to feature requests from bug reports you know you're doing well! :D I asked yesterday but not sure how much you've thought about it, but have you thought about setting up issue tracking software that's community facing? Trac, Github issue tracking, Jira, Redmine, etc. Could be a good idea especially if you're interested in community feedback or visibility in terms of what's in active development. It would also free up some of the meta clutter on #bugski or #hubski.
As an aspiring developer, I'll certainly keep this in mind!feature requests are good signs! once you've crossed the threshold to feature requests from bug reports you know you're doing well! :D