This picture is probably not technically feasible: if it's inflatable and not extremely rigid, I don't see that you would really want to dock anything to it. Consider what would happen if the docking vessel came in just a little too fast: just like any other balloon, the walls would expand as they absorbed the impact. What would that do to the integrity of the module, not to mention anything that happened to be stuck to the walls?
The "proper" approach would be to mount these guys to a rigid hub of some sort, and to dock to that instead. I don't think you'd want any inflatables along the "structural axes."