Great project! Have you seen Nostropus? It does that for notes, in the browser, for a single npub at a time. https://nostropus.com - it wants to be a play-around client for tech-curious newbies and la...
I have seen nostropus, for the longest time I thought this was something for clients to fix (and I still do, clients can auth as their users). For primal and damus, they already do rate limiting, so I think this will be ok, especially since I've set it up to be very respectful with limits. But maybe my IP will get banned, who knows.