We became a co-op not for the sake of it, but because it was the structure that best matched the impact we wanted to have on the world and how we worked together best. In fact, it was only recently that I review the Cooperative Principles[0] and was surprised how closely we've tracked to all of them. Many of these things emerged very organically for us because they were just the most effective ways of working in a highly collaborative way. I find it validating that the way we want to work meshes with a much bigger movement. Yes, co-ops are more rare, but actually there's a huge amount of legal and social precedence we could draw on.
We don't have, and have never had managers at Loomio. We all decide together on an equitable basis how to run the company. I would strongly advise you to find co-founders who really match your vision and sense of deeper purpose. We are a very diverse bunch in terms of personalities, thinking styles, and backgrounds, but we all share a commitment to the same core values and vision. If we didn't, it wouldn't work at all. So if you're working with people not interested in your vision, I'd really rethink that.