By accessing public data sets (including your own GitHub or Spotify data) through Qlik Associative Engine and APIs, you can experiment and create beautiful visualizations and data-driven apps using powerful search, data retrieval without writing queries, out-of-the-box charts with a single line of code and more. Free. Qlik Playground
Figma is more a web UI design tool than an SVG editor, but it has an excellent toolset and produces well-optimized SVG code. Free.
Page Analytics (by Google)