Note stem direction independent for either parts or transposition
Currently, if a note stem direction is changed in a transposed view, it is also changed in the concert pitch view. Equally, if it is changed in a part, it is changed in the score. Where the transposition is different between the score and the part (fairly common for big brass) this means that you may not be able to have both the score and the parts visually "ideal" (depending on your idea of "ideal") at the same time.
The score Stem direction.mscz shows this problem for a motif in B flat with automatic stems. In the concert pitch part the B has a stem in the “bad” (strictly speaking correct, but undesirable) direction. Changing the direction in the concert pitch score, changes the direction in the transposed part. This makes it very ugly.
Ideally, like spelling (Ctrl J), this should be associated with transposition, but a reasonable solution would be to treat note stem direction like any other layout property – independent between part and score.
In an ideal world ...