I like the Shepard for a tow, nice vessel.
The Barrie Model Yacht Club started tug towing competitions a couple of years ago. I've entered them from the start and learned a few things about it along the way. One of the first things myself and sailing buddy noticed were the heft of the barges we had to tow. Although the weight was legitimate based on the size of the tug doing the hauling, the logistics of manhandling such weighty barges into and out of the water was not. We sat down and devised another method of ballasting barges (or ships) that makes the on shore handling by us mere mortals much easier considering our advanced age.
To whit I present the sketch and photo attached. The barge is made of a basic plywood construction, but an open box underneath. A layer of styrofoam is placed under the decking and provides the bulk of the boyancy to the barge. We tried a Dumas Brooklyn with a 3 3/4" prop on the tow, but the tug would hardly move it due to the drag of the open box construction. We then sheeted the underside of the barge with galvanized sheet metal and cut three holes (approximatley 2" in diameter) at the aft end of the sheet metal. This provides a smooth relatively drag free surface underneath, but the holes allow the ingress and egress of water when the barge is placed in, or removed from the water. The barge sat beautifully and gives an appropriate drag. A variation we haven't done yet is to mke a slot in the sheet metal, instead of the holes, and have a sliding gate covering the slot. Therefore the more the slot is opened, the more drag (for bigger tugs) and the more the slot is closed the less drag (for smaller tugs). Either way, when the barge is removed from the water, the water drains out of the barge and the whole can be lifted to shore with one person. and its light to travel with. The same thing can be done for ship configurations too.
oldiron