Here are some examples of work that would be relevant to your project. Empower Girl is quite similar to TED; it’s about ideas worth sharing and ultimately changing how people think and act. With that in mind we created a promo for the event that puts a lot of emphasis on ideas, not on promotion as such: https://vimeo.com/173434557 This got some great traction on social media because it sparked conversations about adventurous minds.
After the event we created this highlights video for their event that got about 25.000 views: https://vimeo.com/182789811/fa6d84cb88
They keynotes varied from 4000-80000 views: https://vimeo.com/178271815
One interesting outcome of our TEDx project was the traction we got with our One Minute Thoughts pilot. The One Minute Thoughts got 114000 in the first week alone on Facebook. The reason is that short form content that starts conversations gets shared on Facebook, which rapidly expands the viewer base. https://vimeo.com/176713858 https://vimeo.com/175901512 What ideas could we share that will spark conversations with your audience?