Before all, as a developer I love Aurelia and its simple yet sensible architecture and its adherence to standards. All Aurelia maintainers and contributors deserve a huge thank you.
I am not a contributor so all I say is under this disclaimer. [Un]fortunately my paid job is full time+ and therefore all my experience with Aurelia is in my scarce free time.
In my job we are developing with Angular. It was an inheritance from previous developers and I learned it on the go. In all honesty I’m not crazy about Angular, but having been developing with it for 5 years I can say that I have very high confidence in Angular, its backers, and the community.
They publish a major version twice a year like clockwork, and in between minor versions with enhancements and bug fixes. Also their migration path from one major version to the next is clear and I have never had serious issues resulting from migration. My productivity is also good.
Their official documentation is not the best in the market, but there are so many written and videoed blogs that I feel I’m fully covered (borrowing from testing jargon).
When selecting anything, be it a framework or a 3rd party npm package, I believe most of us evaluate the options based on the parameters everyone listed in this thread. Namely, frequency of releases, documentation, repo stars, references, etc. On top of the quality of the product itself. We are all programmed to think alike more or less.
Sadly I would not select Aurelia for the company I work for. It’s a startup and like all startups should execute with risk management always on its mind. And this is where Angular (in my case) beats Aurelia.
In a big and solid company where I would feel I could afford to be more experimental, I would definitely advocate and promote Aurelia.