[MattSWilliamson]

I'd recommend Vizzly: https://www.vizzly.co.

It's a low-code solution for customer-facing analytics but is super flexible and extensible with code. Embedding is available in React or Vanilla JS (no iFrames). You can build dashboards programmatically or with the no-code editor.

The backend query engine is also pretty powerful; performant and copes well with complex customer data structures.