There's one thing in particular that comes to mind, and it's that I wish to have more people to discuss fandom with.
And when I say fandom, I'm talking about anything fannish in general. There seems to be this idea nowadays, especially here on LJ, that fandom just means being an active participant in a specific fandom, when that's not necessarily true. My definition of fandom has always been this overall sense of being a fan of something, anything, regardless whether you are actively participating within an online fandom community or not, and sharing that love with others. That's it. Interestingly, that is why I joined LJ in the first place back in the day, because there were a lot of places, communities, and online friends who held the same kind of fangirl gene that I did where we would talk and share our enthusiasm about things. The kinds of shows we watched, the recent movies we saw, our pairings and OTPs, favorite characters, theories, headcanons, etc. That's how I personally connected with people. And I want that kind of engagement to be brought back again. I want conversations and discussions, I want people to share their loves for different types of media they're currently into, their most recent obsessions. It can range from being something deep and meta-y to just simply sharing squee-level excitement.
Basically, I guess I just wish for more interactions about fandom as a whole. Even though the fandom community on LJ isn't as active as it used to be back in the day, that doesn't mean people should be afraid of letting their inner fannish side out.
In the same vein, I wish for more metas in general. Something I always liked was reading people's thoughts, observations, and opinions through their constructive and researched pieces of meta and seeing things from a different perspective. This also helped with the engagement by sharing your own thoughts and opinions, whether in the comments or making a response post, adding more to the discussion no matter whether you agreed or disagreed with a person's points.