My first concern is about debug symbols and automated crash reports, which is touched on in the final sentence:
William Grant asked, in the context of requiring public sources and build logs to be available: Do we want to require debug symbols too?
Automated crash reports are required to maintain confidence in a widely distributed software system. Otherwise you have no idea what’s going wrong or how frequently, because the vast majority of our users prefer to ignore crashes over opening bugs about them (I monitor both). And debug symbols are required to implement automated crash reports. Enabling frame pointers is also recommended for higher quality crash reports, not just profiling.
I think this needs to be prioritised if we want the software in Ubuntu to not only maintain a level of quality but to improve quality over time.