There are several dynamics involved here. Traditionally moving more foil area ahead of the pivot makes the boat feel less heavy on the helm up to the point where it gets too sensitive and squirrely.

I’m not sure if that really changes the relationship of airborne and waterborne forces very much.

Think of a windsurfer where raking the sail forward or aft accomplishes the steering. There is a perfect place where everything is balanced and the boat (board) goes straight, with no helm pressure at all. I would think that this is what you are trying to achieve by changing mast rake. The placement of underwater foils plays into this equalibrium.

Both ways of moving the rudder accomplish the same when figuring points of lateral resistance. Tilting the pivot shaft with shims at the transom will not affect rudder balance and sensitivity. Sensitivity is what comes from tilting the blade forward or aft of the pivot point.

Of course mast rake also affects other things, such as the slot and sail angle of attack which may have a greater impact on absolute boat speed and ability to point.

What does Wouter say?