Untradeable cosmetics are always fun to work towards in my opinion. It’s cool to flex things that you actually have to try for
Another idea I had was to put like a $5 donation to your account after completing x amount of achievements. Probably no epoints, just the donation amount so they can access dz. gives a good goal for players who can’t afford to donate. This also opens up the world of donation perks to people and they might donate in the future. Not sure how well this would work, but thought it would be cool