Some people need "perfect" diagrams, with professional layout.
That is not this tool IMHO, not a dig, its just easy over pretty.. for sure preferance, no judgement.
If I need a diagram for a poster or something, I generate it in plantUML and hand that off to the art department.
Could we add a FAQ that explains this?
I am also not an engrish major so, I leave this to others for wording.