Hi MEB,
This discussion is nearly a year old, see Arrowheads please. . .
I always have to go back to OmniGraffle just to have those "features". I am very sure that your team is very busy i.e. with introducing Affinity Photo lately, but can't there be a tiny "bug fix" upgrade with only those minor improvements? Maybe, I underestimate the deepness of changes what have to be made for the end cap feature, if this is the case I am sorry in advance.
Still loving your App, but I am still away from the point that I can work on the same productivity level as with OmniGraffle for scientific publication processes.
Cheers, L.