I really wish there was something like Tor hidden services, but without the hidden part, just the ability to access something in a performant p2p way with a crypto url. That would make self hosting a bit easier (Although I still wouldn't even think about doing my own email server!).
I had a proof of concept working( https://github.com/EternityForest/hardlinep2p/blob/main/hard...) but it used kivy for the mobile app and I decided I wanted fewer one-person-projects in my life.