First of all, don't expect a "city" because Punta Cana is more an "area" than a city. It's quiet, not too much traffic, almost no cases of violence and personally I find it a good place to work in. Bit by bit we're getting more shopping and restaurant options which makes it a bit more comfortable and a little less "in the boonies". As for what there is to do, you can do almost any water sport, excursions, horseback riding and your normal tourist activities. It's got a couple of decent discos and several excellent restaurants. My only complaint is that everything is a bit far away from everything else but other than that, I'm happy here.
Exactly where are you going to be living?