I really wish the the Horizontal Offset/Width targeting dialog had a button that would automatically assign the same feature line(s) as vertical targets after selecting them as horizontal targets. A simple checkbox for 'Use as Vertical Target' would be huge.
Same with alignments. If the alignment is assigned in the horizontal target dialog the vertical target dialog should automatically select this alignment and show the list of profiles without having to select the alignment again.
Better yet, how about combining the dialogs...