I'll agree with the acts and scenes, but characters? Surely there are more successful pairs. Romeo & Juliet for example.

I was thinking more like Othello or King Lear. In fairness, I did say mostly!

Architects follow onto this by using triangulation to survey and to design.

Maybe somewhat, but we've mainly studied rectangles and circles as being in perfect proportion to the human form.

Yup. Leonardo's The proportions of man is a good example of this. (Incidentally, it is the design on the back of the Italian Euro coin).

I did architecture in a fomer life and it is near impossible to draw a square without a 45 degree set square triangle). You can do it with a compass BUT you need to centre that circle first and that requires triangulation.