I think the goals of this project are really noble and well described.
Given that you have a live website already, I would love to hear more about your thinking on execution as part of this pitch. To what extent is your current website succeeding at your goals? Have you succeeded in attracting *and retaining* users? (my intuition is that user retention would be a potential big barrier to success - what makes someone come back? so I'd like to see evidence that this is something you're either working on or have evidence it's not a problem)
Basically, I think the project is cool and I'd like to see as part of your pitch a concrete assessment of where the bottlenecks are because that should shape your next steps, and give the partners you are looking for confidence that they are joining a project with longevity.