These guys make a great trailer, but any trailer that looks like this is going to work the best for rafting. Flat Bed, but big wheels and tires for long high speed trips. Waterproof LED lights, rollers on the back and a winch.
I did the whole utility trailer thing for a while and it was terrible, it sucks to unload stuff and then pick it up s heavy ass raft to get it up on the rails. Then you think its a great idea to throw your cooler and gear under the raft but then you can't get to it with the raft on there. Now I just back up and winch the raft onto the trailer fully loaded and take off.