Now that I think about it, creating an online community (at least one that is decentralized or have loose-to-no moderation) is kind of like raising a child. You may have a vision for your child. You may try to raise them on certain values, but ultimately the child will choose his/her own path.

Same thing with starting an online community. You may have a vision for said community. You may try to impose a certain culture, but unless you impose strict moderation, the culture of said community will grow out of your own control. I think this is why many people who create forums, imageboards, or social networking services end up getting disillusioned with the whole thing. It becomes something that they never intended it to be. I know a lot of libertarian-leaning people who create free-speech sites, but end up being shocked when they turn out to be dissident right echo-chambers.

You just need to realize that culture is 100% organic and grassroots, you can influence it as much as you want, but people will ultimately be the ones to make of it.