I would like to create extensions for some components already deployed in Angular 2, without having to rewrite them almost completely, as the base component could undergo ch
Angular 2 version 2.3 was just released, and it includes native component inheritance. It looks like you can inherit and override whatever you want, except for templates and styles. Some references:
New features in Angular 2.3
Component Inheritance in Angular 2
A Plunkr demonstrating component inheritance