Cool! Have you checked out https://github.com/bvaughn/react-virtualized too? Might be totally useless to you, but I think they've done a lot under the hood to optimise table loading.
I’ve used react-virtualized to render hundreds of thousands of rows, it’s a great library. React-window from the same developer is also worth checking out if you don’t want all the bells and whistles.
Congrats again on a beautiful product.