There's a good hours work in making an accurate footprint like this once you get the hang of it, but the effort will pay for itself later on during documentation, layout, and just that warm fuzzy feeling when you show your files to someone and get that inevitable 'wow ... are you taking your medication, cause that footprint is nuts!'

Aside from great looking documentation, though, the biggest benefits really are on the mechanical side.  Need to know exactly how to align part of an enclosure to a button or a trimpot?  The extra hour you spent making that footprint will seem like time well spent when you can quickly determine with excellent accuracy where the screw head on the SMT trimpot is!