No need for a bridle at the boat end. Two points to make.
Add a third line
from the dingy bow handle/tow attachment ring to the bridle. Adjust this line
so it is just long enough to take up the force of a pull directly ahead. It will then also take up any non-horizontal pull. A problem with the bridle lines
to the side D rings is that if you tow the dingy through rough wave action for a day or so, the bridle lines
will rip the fabric tabs holding the D rings right off the inflatable tubes - these ring attachments are not designed to take loads off the horizontal. A short center line ensures the only pull on the side D rings is generally horizontal, whether to left or right, but not up/down.
The second is to run the dingy tow line to a secondary winch
, if you have one. You can then easily adjust the length of the tow line if necessary even when underway. You should shorten the line whenever you anticipate manovering or stopping, such as when entering a harbor.