Slur/Tie placement

In the preferences area, the user should be able to dictate +/- spacing for the default slur/tie positioning. Often times a slur can be desired to be 'a little over' the span of the notes, or for another example, when slurring and tying one after the other, often a slur's being shortened makes for an easier reading. Something as simple as a default depletion/addition % for anchor points would work, and can't think of any reason not to have this as a feature in the preference/settings for ties/slurs.

And while we're at it, another option that might be useful to have in the future is to edit simultaneously both terminal points of slurs so that the user can extend or contract them quickly. Not sure how it would be implemented exactly, but it could be slick if done appropriately.