Listen before everyone runs in here attacking me, telling me how I am playing the wrong game or whatever, please hear me out first.
We live in a mostly negative world, what I mean by that is we live in a world where people like to focus on what can't be done far more than what can be done. As I write this out I am almost 100% sure I will receive more replies about how combat would not work in this game rather than how it could work. However I believe that a true sandbox game should be with as little limits as possible. Why not have combat? Who does it hurt? The truth is it would be simple to implement without hurting anyone. I am sure there are plenty of people here who just simply want to enjoy a social experience, but why not have it all? What I am suggesting is add a couple areas for player who want to battle enemies (possible each other)?
The players who don't want to be involved in anything related to combat would never have to go there. It could work and Im pretty sure the intelligent developers could work it into the lore/world. This game has a non violent feel to it, but there are forms of combat that are not as violent that probably would work here. For example, if you wanted to do a sort of pvp system, you could have laser tag, or foam sword (weapons) duels. As far as pve you could add new enemies in the newly made battle zones and add a hunting skill for player want to go out and hunt the monsters, maybe get resources from defeating the monster that would some how help the community like everything else in this game.