Personally I'm no fan of topic-specific relays.
They increase complexity and decrease censorship resistance.

I'm for interchangeable general relays which don't filter beyond what they need to in order to protect their utility or existence.
Using many at once is trivial and grants censorship resistance. 

 Nostr has communities, too.
They serve a similar purpose as topic-specific relays, but do it better in a simpler manner users already know from Reddit.