That's something we've been working on lately. A month or two ago, the only hostile animal around was the Rar. In the coming updates we'll be adding not only a few things for players to do around town (cards to play with, balls for sports, etc), but we're trying to devise something that not only gives people things to do away from home, but gives them an incentive to do so, while still keeping the open ended RP as part of the game. Replay value in Haz has been the hardest thing for us to improve, and any ideas are more than welcome.
Well I was (and still am) contemplating running around out into the wilderness, building chests and filling them with coins and other valuables. Why? Because _everyone_ likes finding hidden treasure. Can Hazordhu handle random distribution of objects? That's an easy one to do right there.
Second I guess would be that there needs to be more markers of wealth. The trade barter system is cool, but all you really have beyond that are metal coins. Gold, gems, the things that people desire for their value, would help liven up the surroundings, add more of that "I found secret stuff" joy and be another engine of RP. (Gold deposits, currency wars, banking yadda yadda.)
And lastly, as always,
hand crafted content to explore that's got something going behind it. The Undead Fortress was a neat exploration experience, it lacked mobs though when I saw it and the design was a little repetitive. But the imagery was cool. More of that, not necessarily on that big of a scale. Mini-dungeons. Lairs for really nasty beasts that don't just wander at random. That jazz. The flargls and what not are the precursor to that, because randomly roaming uber death is always fun.
Those are just the generic ways you could go, off the top of my head.