1. Either channels for keeping stuffposting contained, or just a rule against it. Because if I want to have a conversation, I don't want to have to sift through reposted memes to find what people are trying to say.
2. The better the organization, the more likely I am to stay. I like being able to mute exactly what I don't care about.
3. A reason for me to be there. Some are just developers I'm keeping an eye on. Some are small communities or circles of friends. One is BCC.
It doesn't have to be active. I have things I can do other than sit in a discord server all day. It's just something that keeps me connected and sits in the background.