Thanks for the prompt and thorough reply. I understand #2 being a part of the technology. Just like when you post on Steemhunt or Dtube it posts automatically to Steemit also, because Steemit is posting the entire steem blockchain. I do think that is going to limit the forum use somewhat. There are a lot of private forums out there. I would argue that the forums with the most active users are often private, outside the tech space anyway. It will be important for you to make it clear up front that you are offering exclusively Public forums.
Still, good luck and I look forward to getting to spread the news once you're ready for primetime.
yeah...there isn't much we can do until hivemind is out which I believe will open the possibility to have closed communities. https://github.com/steemit/hivemind/blob/master/docs/communities.md
Actually from that link it sounds like even with hivemind their intention is transparency and the inability of community founders to censor outside their own community. They make no mention of privacy protection. So sounds like it will be 100% public communities, in terms of no expectation anything you post in a community will only be seen by community members.
That's all and well, just important to make clear early on. It's better to immediately disinterest people who have privacy focused communities than to get them excited, then dash their hopes for getting to monetize this way themselves.
blockchain(public ledger) and privacy seems to be a weird combo to be honest...especially when it comes to content.