The API seems much more intuitive than that of D3.js!

I used D3.js originally to draw line charts to visualise USGS mineral statistics, but currently only use it for svgLine (from d3-shape) and scaleLinear and scaleLog (form d3-scale) functions.

Is drawing on canvas much faster than on SVG?

Could matrix or other transforms be used to map screen coordinates to chart coordinates as the d3 scales do?

Generic projections in complex plane (viewed as cartesian or polar coordinates) might be fun for generative art or visualisations of various signals.