Make spline edges end in vertical slopes

[keyserj]

Describe your issue

Recently, functionality was added to draw edge paths based on the output of our layout algorithm. Unfortunately, the layout output does not result in vertical slopes at the start and end points of each path. These vertical slopes often seem desirable, because they go with the top-down flow of the diagram, and without them, the edges can look a little haphazard.

These simple edge paths all end with arrows directly upwards, which is nice:

These edge paths based on the layout algorithm have some of their paths starting/ending at sharp angles, which is awkward:

Solution you'd like

No response

Alternatives you've considered

No response

Additional context

If we did this, I think we should be able to remove the "Draw simple edge paths" config, and just always use the layout calc's edge paths.

Technical ideas and questions

No response