1) Are we talking royalties for (i) a single produced work? Ex. I get 1% of a particular book that you're writing or publishing. Or (ii) is it 1% of all future royalties from any written work that you publish? In the latter case, the legal framework will get rather convoluted because you'll need to define the exact scope of what is and is not covered (what about monetized blog posts? what if you shadow write for another author? what if you write a screenplay? etc.).

2) Have you looked into SEC regulations regarding setting up such a structure? I'm not 100% sure how it works for films, which often option off royalty rights to all kinds of people, but (i) above would be a bunch of individual contracts in a similar manner. However, in case (ii) above it seems you would essentially be setting up a corporation for yourself that contractually owns your IP and receives royalties on it while issuing shares to others.

3) How much creative control do shareholders get in exchange for shares? Basically, are all shares non-voting, or if I own rights to 51% of your royalties do I get to tell you to stop writing alternate history novels for adults and hop on the sappy YA train instead?

In any case, I like the idea since it takes the concept of Patreon beyond the "well-intentioned benefactor" level.