This site is just way too diffuse and has too few real people actively participating. It is also missing some very basic things that would accelerate engagement. Right now, your profile doesnt tally your upvotes. This should be a pretty simple fix and would promote visibility into who the top contributors are and the perceived quality of their upvotes.
Organized events would also keep momentum going. I remember back when reddit had AMAs that were actually interesting and fun instead of thinly veiled opportunities to plug a recent project while talking to someone's PR manager.
The aesthetic could also use a revamp. Nothing tailored to smartphone usage (blech), but maybe something that fills the screen by default, and improves readability? Comment sections are less easy to follow than on pre-IPO reddit. Native hoverzoom would also be nice. Is there anywhere to actually have an exchange with the people running Lemmy?