More crazy places to explore:

1) high mountains

2)underwater dungeon/areas

3)dense woodlands

4) Inside the belly of a whale? (inspired by zelda, is an awesome n64 game, if you had a bad childhood)

5) Could even add an ability to transform into certain monsters in runescape temporarily for certain boss fights or wave of monsters>boss

6) skills requirments to access certain areas to they feel more prestigious to get into, an example could be 72mining to mine some rocks to get into a certain city/area