Thanks. I may reconsider and start off with Postgres. I want to make a command line tool that anyone can download/run to get metadata and statistics about relays and interactions, hence wanting Sqlite for ease of use. It should give info that's more in-depth than a normal client would show, but not a monstrous Hadoop thing. I want it to be able to answer questions like, "Is such-and-such relay dropping my events specifically, or is it broken?" or "Which relays are filtering such-and-such words?" But I also want it to be able to reconstruct conversations, social graphs, and trends eventually to prove that Nostr is one big circlejerk or to find the pockets of people who don't just talk about zaps.

Sounds like Postgres is probably the way to go. It supports arrays semi-natively, too, which may help solve the nip01 tags problem a little more easily.