I'm sorry if you feel that "Forcing" some world exploration is a bad thing, personally I think it should be part of the adventure. I understand you Risk Vs Reward system and I think it's a great idea I looked the thread over earlier and can't find anything to dissagree with really aside from it being extremly time intensive to implement such a system that catter to everyone.
I think it's better to "trick" players into exploring by having your content divided up between different sections of a given area than it is to "force" it upon them by making them take the long way to a given destination. If that sounds like a "theme park", it's because it is, but it's an effective model for a developer if one of your goals is to, at the very least, get people to go near the places where you've put all kinds of cool stuff; from there, you can add elements to the area that will gently nudge the player in a given direction without outright forcing them to go that way to finish their mission. Something as simple as the lighting in an area can accomplish this goal, but I'm sure there are other methods, like additional mobs.