3. Safety versus standards.

The dichotomy feels very specific to companies. I don't see why most communities couldn't have both, with people simply having various levels of engagement.
Most communities have a lot of idlers and lurkers.

I strongly disagree. All communities have to face up to this tradeoff in one way or another. Just as one example, the LW community has been low-key having this debate for a long time now; "should we be about Being Real Ambitious or just focus on being nice to the people here?"

Hobby communities have to think about how much they prioritize Being Good At Hobby vs. Just Having Fun. Church communities have to set standards of behavior and parameters under which you can say you 'are a member.' These standards and priorities for things other than community cohesion often mean that individuals feel less safe (if I'm not Good At Hobby I'll be ostracized! if I do [church-disapproved behavior] I'll be ostracized!), but serve other goals for the community that are also important.