Sounds like you should be the platform and let content creators in. Pay them commission on sales and you can QC anything coming in until you can afford to pay someone else.
It's definitely something we considered! We actually were really focused on that for a long time, but didn't get a lot of traction with it, because creating content in our format requires illustration and animation, which is not easy to do. A lot of people said they wanted to do it, but very few followed through. We did some partnerships with media companies but we didn't solve a critical problem for them (the original inspiration was the end reader experience) so there was not very much urgency or willingness to pay. So we pivoted to a "full stack" model where we create the content and build the platform. It was working decently well (it's not easy to get 1,200 people to pay for access to content), but just not well enough.
Have you tried creating a 'creator's' software that's lightweight, easy to use and has lots of pre-loaded illustration packs (with a wide variety of themes) & drag-and-drop style animation presets?