We really enjoyed the Ceran St. Vrain trail. There's water the whole way. Plenty of spots to hang. We heard that there were usually a lot of day use folks using the trail. We went late September and it wasnt too bad. When you hike all the way back to where the four wheel drive trails start there is a nice little aspen grove you can get 3 hammocks in. It's right by the water. You might even see a moose.
Here's a link to the Forest Service site.