One challenge that I can see for a community-driven project is that so much ideas and opinions are being laid out, that makes the development bit slow. So I think, even if this one is community-driven, the dev team should somehow interfere and decide what's gonna be next. Thus, the project will not be stagnant for so long that everybody wants their opinion to be acted upon on.
I would agree with this.
I don't have heaps of experience, but with other community projects I've been involved with this is often the case.
Ideally, I would say the roles should be "layered" somewhat. The main devs and a few key community members could have a private channel to discuss and plan core concepts and features, but ideas can still be voted on by the community.
Tricky to balance this, but it is certainly possible with good project leads.