Move details, especially of quality requirement, to this section 10.

Here you have the quality tree (section 10.1) as an (often graphical) overview, and the quality scenarios (section 10.2) as a collection of many (or all) additional quality requirements.

We participated in the development of several systems having more than 100 different quality scenarios. In such cases, arc42 section 10.2 is the right place to document these (if they are not contained within written and easily accessible requirements documentation).