I’ve used Angular Material with great success in 2 projects. I found few issues as it neared 1.0. The # of issues on Github has more to do with people trying to use Github issues for assistance than the quality of the product and is reflective of the large number of users it already has.
I do agree that it is a bit lacking in terms of some components, but found it to be more complete that MDL or Materialize, which I also evaluated. Additional components would be nice, but many of the existing components can be used for multiple purposes. Your Materialize based responsive navbar looks exactly like what one can do with md-sidenav. md-toolbar is easily used for responsive headers and footers. Collapsible content is trivial in angular in general (and shown within the sidebar on the Angular Material home page). Chips seem like they could be used easily for badges. The lack of an md-data-table implementation is the only drawback in terms of missing components that I encountered. Daniel Nagy’s md-data-table (https://github.com/daniel-nagy/md-data-table) has been an indispensable addition to development with Angular Material.
Personally, I’ve found that for those well-versed in Angular that Angular Material is a great fit. I would expect that as it migrates to Angular 2.0 we’ll have a great deal of control over what’s loaded and when.