I made a workaround for this situation, but I too found it to be a pain.
+"Move Left" is down
+Not "Move Right" is down
-Player: Set angle to 180
-Player: Set acceleration to 300
++Player[Platofrm].VectorX Greater than 0
--Player: Set acceleration to 1500
Perhaps the behavior could include a feature like this by default? Even better than just setting the acceleration to a particular number, you could make the turnaround acceleration to acceleration + deceleration.