@naaate
There are a few things that I feel like require finding the right balance, the main one being "providing a vision" and "getting input from the community." There needs to be enough vision that the people who align with it can get excited, but the more that the community can participate in crafting the direction, the more they feel they are deeply a part of it as well.
Another is "incentivize participation" balanced with "low barrier to entry". You can't have the incentive be too high, especially relative to the barrier to entry. And of course you don't want the incentive to be too low.
I also think only certain kinds of "mini projects" will work. I think the best mini-projects would be a small part in a long term vision.