Not sure if going forward with Angular.js was the right choice, given Angular 2.0 had been announced, and will be different from Angular 1.0 (no backwards compatibility)
There will be a clear migration path, including, it seems, the ability to run both 1.x and 2.x modules side by side using the new router from 1.4. This means you won't have to rewrite your 1.x modules immediately. 1.x also has a commitment from the Angular team to remain maintained for the foreseeable future.