When you go back you can gently encourage those folks to come here. If you aren't interested in modding a community here, you can ask the mods of those subreddits to start them.
There's a lot of chatter about joining the fediverse in subs like /r/RedditAlternatives, but you don't see people talking about the selling points in those small subs. You can start those conversations. Maybe there's no takers, and that's fine. But if you like it here theres a good chance others will too.
Sokay i'm starting a new instance symmetriclemmy.world
There's a few where the classic post is a reply. I'm not sure what the best way to format those would be but it would be great to have them be consistent. So here's an example, though the joke has been done to death, the orginal should be archived.
phil8248 (17.9k points): I'd like to have sex one more time with my wife who passed away from cancer 9 years ago. My body yearns for hers. The ultimate downside to finding "the one" is she may die young and leave you wanting.
somethingobscur (27.7k points): I also choose this guy's dead wife.
it's that dodad with the four lines above the 3 key on your keyboard