The initial requirements include a virtual space to exchange ideas and capability for online brainstorming. Have a calendar of events and news of what's coming up. We also want to connect people with experts in particular areas if they need help for a project. Have a virtual tour of the space so that people know what to expect and hopefully entice them to come. Disseminate outcomes of projects and showcase any achievements.
Like an aquarium, it will need ongoing maintenance and attention but the outcomes will be worth it. Let me know if you have any other ideas.