But most people don't respond to that. They are more likely to report problems than success as well.

What you want to do is just observe, and anonymously report. Some packages themselves will know if they issued any diagnostics above a certain danger level. In addition, you can tell the difference between a package that after install is regularly used, and one that is never used or used briefly then stopped.

Though indeed, it doesn't hurt to have a system to ask, from time to time, for the user to review the success of recent packages, done in bulk rather than one at a time. Ie. "We see you recently upgraded these. Please check any you noticed problems with. If you care to be more detailed that would also be very helpful." Then anonymize and upload to database.