I think there's a good chance people will leave once Lemmy integrates with Threads. So if you time things wisely, you can probably get a good base of users to swap their coms to Sublinks.
What's your planned policy for karma? I know users hated it, but as a reddit mod I found it super useful to determine between a misinformed user and a troll. If your plan for mod tools is as good as you're saying, I wouldn't mind going back to modding.