A possible model is to divide your shares into ownership/control class shares (reserved only for workers) and profit shares which can be bought/sold by third parties. This gives workers ultimate control over the venture while allowing third-party investment. I don't know if this has been implemented anywhere, but it's a possibility. It's not going to fuel explosive growth like VC funds do, but TBH I'm finding as I get more experienced that those types of ventures generally end up being trash dumpsters once the honeymoon phase is over.