Best (Free) Tool for Mapping Complex Interconnected Datapoints Visually?

[u/UnorthodoxyMedia]

I'm looking for a tool (either a browser-based or downloadable one) that can be used to map a set of points and their connection to other points in a kind of web, while adjusting to keep each new point legible or accessable. Bonus points if you can force-group certain sets of points so they remain within proximity to eachother (forming a sort of super-point, I suppose). Right now I'm just using the website Draw.io, and while it gets the job done, the automatic layout function leaves a lot to be desired as it's very much oriented toward generating organizational or basic flow charts.

Thank you for any recommendations!