Interesting. Why not use an open link network? These will result in around the same state. Spam _will_ be an issue here, in general. And with a different backend you're going to struggle to use preexisting tooling to handle it.

Using & channels is fun, I'd be interested to see how many bots and clients fall over dead when faced with that particular bit of IRC history.

IRC linking is a mess, in part due to the spanning tree requirement. Also the server to server protocol in the RFC is spoken by zero servers so you have to pick which unofficial protocol you like best. May as well invent your own that actually fits your use case.