[mgechev]

Hey, Angular team member here.

The decision to use Observables was made after an extensive discussion. You can follow the thread here https://github.com/angular/angular/issues/5876. If that's an interface that doesn't align with your expectations, you can use fetch and/or wrap it in a service to take advantage of the DI mechanism we provide. Another popular third-party solution is https://github.com/axios/axios.

There's a straightforward way to export components to be used by a third-party app directly via the Angular CLI. If you'd prefer to use a component outside of Angular, we have @angular/elements.

Hope this addresses some of the concerns you had.