Honestly I wish there were less communities. I've said this before, but people treat Lemmy like late-stage Reddit, expecting niche communities for everything, and we end up with hundreds of communities with no (or one, if we're lucky) active members.
This problem is then amplified by the fact that these niche communities are split even further across several instances, so our userbase ends up completely dissipated.
I would love to see users focus on a smaller number of more general-purpose communities. Of course, these should still be shared across instances, but I think we would benefit a lot from having, say, a "video games" community instead of 500 specific game communities.
As a side note as well, I don't think we shouldn't be "allowed" to create more niche communities (though if an instance admin wanted to regulate, that's their call). I think this should be more of a user culture shift, if anything.
I just want the communities that already exist to have more engagement. It's pretty demoralizing making a high-effort post and getting only a handful of upvotes and no comments. And it's like watching a hospice patient visiting a neat-sounding community and realizing all the posts are by the single moderator (and are getting less and less frequent).
I think one of the best ways for folks to contribute to the health of Lemmy would be for everyone to spend some time on "all - new" (or even "all - top hour") on occasion. "New" on Lemmy is not the cesspool of reposts and garbage that it was on Reddit (although there is a LOT of porn if you don't have NSFW toggled off), and the quality of the first few pages of "top hour" is usually pretty good (except again for the porn, which it turns out gets pretty decent engagement). I visit "top hour" pretty regularly, and nearly all posts that are stuck in zero-engagement/minimal-engagement pergatory are simply niche content rather than bad content.
I miss the "Tales from..." subs. Tales from tech support was regular reading material for me for many years, and in general just having a place to commiserate with others in the same field as you is wonderful. The other ones also helped me be more concious of what I could do to keep myself from being a nuisance to other professionals like my doctor and pharmacist.
More niche, I miss the gunpla sub a lot. We have subs for model making and tabletop miniatures, but the gunpla community was very well run.
In general, I think the lack of moderation tools has made it difficult for communities to do regular "event" posts and the like which used to really help keep subs alive, guide discussions, and gave good examples of the type of content that fit. Like it's a lot easier to start a new conversation at a party where everyone is talking than to be the first person to speak up in a silent room.
It's really not possible unless Lemmy gets a much larger community, but the thing I miss most about Reddit are episode discussions for TV shows. For almost any show, I could be pretty confident that I'd be able to find a post-watch episode discussion. Those are great for seeing how people felt about the episode or to learn things I may have overlooked.
I’ve had an idea for a community based around recommending music to each other; you’d post a song or band and get recommendations. Basically a Build my Playlist community.
I miss the non-porn nudes threads, Normalnudes and NakedProgress, the ones with an "if you can't say something nice, don't say anything" policy where people of all body types could show their shape and/or their fitness progress.
I wish there was more sports engagement, specifically college and pro football. It’s about the only thing that keeps me going back over to the other place.
/c/DSP. Digital signal processing, i.e. how to transform, filter, and live with digital signals (e.g. audio files, image files, video files, sensor measurements, etc.). It involves a lot of math, so unless we get R*ddit-like numbers I don't really know how such a community could keep moving.
I really want there to be a community for Dropout as I love their content but I haven't found a good space to talk with others about them that doesn't involve some corporation harvesting my data.
Pathfinder_Kingmaker. I spent ages talking about builds and strategies on that reddit sub. I still miss guiding new players into the games. The BG3 community is the closest I've found but it doesn't scratch quite the same itch due to 5e's simplicity.
Pathfinder does have a few active communities but they are all for the tabletop. The one for the game on Lemmy.world is dead as a doornail.
Enlisted (the video game). I enjoyed the discussions on the subreddit. It's already got a small community, so it's no surprise that it's nonexistent on Lemmy.
i wish a lemmy community existed like r/wordington with unhinged content. And more communities dedicated to games, which are active like a Terraria community for instance.
JapanLife and JapanFinance. Tons of knowledge for people living in Japan where language, the legal system, etc. all are much easier to navigate with the help of people who have been here. They never really got off the ground in the fediverse and are the only reason I still go to reddit.
InfoWarriorRides / SchizophreniaRides, for pictures of cars with batshit crazy messages on them.
100YearsAgo could be mirrored here via bot and not miss much.
Other subs were great for their discussion more than than linked content - Civvie11, GunnerkriggCourt, DresdenCodak, QContent. Not so much DumbingOfAge because it devolved into a hatedom sub. I guess most of that should be lumped into comic and game-video communities. I could "be the change" and start posting speedruns willy-nilly.
An active box office community. I don’t really watch movies but I enjoy the data and the discussions about why movies are performing that way. @ClarkZuckerberg@lemmy.world tried to singlehandedly keep it afloat for some time, but it didn’t work unfortunately.
I imagine it’s like sports statistics but with a lower barrier of entry, and sometimes you watch a film franchise you enjoyed die in real time.