Could there be a one-click way to automatically ‘import’ a Reddit subreddit over to a Lemmy community? Meaning, create it, import the sidebars, welcomes, rules, graphics, etc. so it looks familiar to regular users. If not, at least a step-by-step tutorial on how mods could do it.
Another option would be to provide something like a crossposting Chrome or Firefox extension that lets people simultaneously post content to both Reddit and Lemmy. Give them a smooth transition path.
Lastly, the Bluesky concept of ‘pluggable algorithms’ is one way to make it so users can choose whatever sort works best for their interests.