I think a very fun mental trick Paizo does in #pf2e is pinning the amount of XP required to level to 1000. This removes a hard-coded XP value from every single monster and hazard in the game and instead places them on a sliding scale directly associated with the average party level.
When the GM is designing encounters, they are required to keep the encounter within the bounds of what the party is capable of. I can also quickly tell that a 260 XP encounter is 26% of the party's way to leveling.