robot on Nostr: This way it seems very feasible to me. I am not familiar with NAT punching protocols. ...

This way it seems very feasible to me. I am not familiar with NAT punching protocols. Also, if we think about it we could save a lot of requests to other relays and thus make them smaller. It makes sense as you put it.

If as a developer I can help in some project like this it would be great. Since having your own relay would make custom filtering of information much more feasible. I'm not talking about a filtering based on likes like traditional social networks, but a fully customized and configurable filtering.