Looking at Tahoma, I see that it places the macron over the L dot ($1E38) centred horizontally.
I prefer the macron to be to the far left, centred over the upright of the L.
I also use a narrower macron to compensate for the narrow stroke, and in lowercase ($1E39), which is centred. Likewise, with ī macron and Ī macron.
Should Macron be Left or Centre? Obviously it should not be on the far right.