But for non-programmers, I would say that user-friendliness is very nearly everything. They are never going to keep the "simple" underlying model of an directed

But for non-programmers, I would say that user-friendliness is very nearly everything. They are never going to keep the "simple" underlying model of an directed acyclic graph in their heads to let them intuit how to work with it. For them, they need an interface that baby steps them through the process and makes it obvious what to do at every turn.