I'm definitely in support of "mega-threading" anything related to the Reddit blackout unless it's big breaking news (but mega-thread those events too).
I've also started to look for communities for some of my interests, but I suspect it's going to take a while before a lot of them spread to here. There are also a bunch that I can't really start since I am primarily a consumer and not a producer (specialized topics like astrophysics that I am not a subject matter expert for).
I've been toying with the idea of starting a physics (astrophysics welcome) community over at https://normalcity.life/(my home lemmy instance) for physics academics. I'd love a community like that because it's my everyday life. Does that sound interesting? Not sure if others would be interested.