Use ChartJS or Vega to render charts instead of Google Charts This should increase load speed for large graphs and will also provide more flexibility.

Use of JavaScript frameworks needs to be avoided since Maven reports are file-based and can only consist of HTML and JavaScript.

Compare
https://www.chartjs.org/docs/latest/getting-started/ and https://vega.github.io and https://gionkunz.github.io/chartist-js/