Interesting points. Tried similar myself many a time. There is also the option of buying a trailer extension.
These come in many types like one with a tow ball to fit into the trailer and hitch the other end to click onto car (but these can be very difficult to reverse with having an extra pivoting point). check out eBay item number 110690429731 for example
The better one is a system which folds out when needed from storage along/inside the drawbar of the trailer. It secures to the winch post bracket and simply extends the length without having to remove from the towing car
Links for some examples
The cheapest quick fix is the last link and pictures which supplies a cable system (safer than rope) around £65 delivered
Hope that helps
Peter @ Boatsandoutboards4sale ~ email@example.com
~ 07930 421007