Guild Wars 2

Place certain chests and tough creatures in areas to reward exploration. This is done is some areas but more of it could be done. Put them off the beaten path, in places where people just following an event are likely not to go. Some way to reward those of us who still like to adventure into the unknown looking for that rare monster or rare chest.

Example:

I have seen many sunken ships that would be good place to hide chests, they could be full of gold or items etc.

Make hidden areas in on mountain sides that require exploration to find, maybe at a little flashing area that you can use your mining pick and you dig in there and find a cavern to explore.

Place hidden items underground or better yet make certain areas where you just fall through the ground, like a trap and then find you need to explore this area that this worm dug to catch prey.

Those are just a few I can think of you guys/gals seem very creative. Lets make this game challenging. The tough jumping puzzle for sunset cove was nice, the harder something is the better the reward.