Diagrams is not just Archimate and UML in Visio. Via a colleague I came across this excellent freeware tool draw-io. 

Draw-io offers various features, incorporating a wide range of elements, such as basic shapes, arrows, stick figures, etc. While using, you can create simple sketches, professional diagrams, and even customizable flowcharts.

Suddenly, everyone seems to use it. Just nobody told me. One of the diagrams, you can use is swimlane diagrams, but apparently you can also make excellent Azure flowchart diagrams. Here is an example: