I've mentioned this before, but I only see upside to getting the experience as you go.
Walk in the room, you get 100 experience points.

The vets know exactly which rooms they are already and so nothing really changes for them. But it would help new players learn where to go.

Maybe you want new players to walk through every room of an area on every character? But I am sure, they don' want to. It becomes a drag to walk in every room over and over again on different characters. And when you do explore that area on the first time, it's more exciting to find them, like easter eggs.

You just create an incentive for people to write walk through scripts or repeatably log off/on to check for exp hits.

Explore points behind mobs you have to kill are good, you have to be strong enough to get it and would be nice to get your reward as you walk past it.