Honestly, all they need to do is make it so nodes dont lock out after you run the map.
This way, you go out, find all the bosses and stuff, and then when youve "finished" the atlas by finding what you want, you can just socket a new waystone and rerun any layout with extra content over and over again just like poe1. Unique nodes like paradise and seer get locked so you could keep expanding and running outward to find them as incentive to keep expanding, or just run the node you want over and over with a new waystone.
You still need key fragments to run the pinnacle bosses, its not like you really need to find another citadel.