In relation to this discussion on gitter:
I’ve had a look at this and observed something mathematically rather intriguing. For base 10, distances to subsequent decade tick marks all seem to be 90% of the 0-1 decade distance. There is a clear mathematical relationship at work here, as shown in the diagram below, which uses the code from issue number #10369 to generate the graph which I’ve annotated manually in Inkscape.
Is this an intentional part of the scaling design or should tick marks be equally spaced for all decades?