What would be cool is if you had a series of caves targeted for the lower level players; groups of 2 or more suggested but solo-able if you're on the higher end of that particular cave level requirement. Limit the entry by the level of the character. It could start out as a grand cave with different paths to take depending on level: 7-9, 8-10, 9-11, 10-12, and so forth. Rewards could be pots, or create a new collection, or offer a free repair on armor w/o durability loss">.