I suspect ipfs folks would be interested in collaborating on some of those tasks

I do think a collaboration's in our future. Right now I'm talking to @mafintosh about Hyperdrive. Hyperdrive and IPFS both have strong tech and talent behind them, but IPFS has traction, while Hyperdrive has a smaller surface area and less functional overlap with SSB, which makes it a nicer fit. I also know @mafintosh a bit more, personally, and trust his engineering. There's nothing forcing one or the other, though, and if there are IPFS experts on hand, ping me so we can talk about it.

The matrix.org folks would be interested (and are working on) this.

I'd be interested to talk to them. What's a good way to get in touch?

Personally I'd be happy if patchwork ran a local server that I could use with my normal browser.

UI in the browser?