As is often the case with aerodynamics there is no definite answer. Especially not when it comes to compromise solutions such as adjustments of the engine thrust line.
I make decisions about the thrust line only after flying the aircraft several times. If I find that I have to apply right rudder more often than not in different maneuvers I add some right thrust to the engine. For me the correct amount of right thrust is what minimizes the need for right rudder corrections during a typical flight of the aircraft. Typically I seem to end up with 1-2 degrees of right thrust for my 3D aircraft (.40-1.2 cu.in. size).