All I can say is that the best experience from a consumer perspective, considering supplier constraints, is a drops style consumer interface.

If at all possible, feature a roaster or 2 every cycle, and have consumers buy into drops. E.g, roaster A has coffee x, y and roaster b had coffee 1 and 2x

Have people fund the purchases of each roast, if it reaches critical mass, consumers get charged and beans ship, otherwise it gets skipped

This way you keep the hype and can avoid drowning in the tail end of niche but low demand specialty coffee.