How should Lemmy sort posts so small communities can compete?

Right now, big communities dominate the feed. I’m wondering what sort algorithm could level the field so niche or hobbyist communities have a fair chance to get seen.

There’s a good related post: Niche Communities won't be able to reach their true potential until Lemmy adds a sort that takes engagement into account. It puts it well:

“If Lemmy is to truly start having active hobbyist communities instead of being 95% lefty US politics, Shitposts, and some tech stuff, it needs a sort that takes into account the user’s engagement.”

What do you think should be the default sort for a more balanced Lemmy?