The back end will be Node, talking to Mongo and Azure SQL Server. The data is imagery overlays on maps, and dashboards. I'll be using Mapbox and probably PowerBI embeds.

The question is this: which framework/library should I use of the above 3? Ideally, this should be something that is easy enough to learn and extend, intuitive and easy to maintain.

I've built a few learning projects with Angular 2, have an ok grasp on the basics, but it's a bit of a monster.

I've heard many good things about React with Mobx and Vue. I think that pretty quickly, once the MVP is built as a browser app, I'll end up building it as a mobile app, using Ionic, Nativescript or Jsonette. A point in Angular's favor is that it lends itself to making the app in Ionic.