On my local Moodle test site I often play with roles over-rides (at site or course level). However, when I went to trace the changes I have made, I think the interface would make things easier if those capabilities I have changed (from the default setting) were displayed more visibly.
In the above example, when reviewing a role where I have made a number of changes, it would help me trace those changes if the Add a new quiz "Allow" cell had e.g. a light red background (or other).
Also, the site roles editing interface features a useful "reset" button. I wish we also had a "reset" role button at Course (or activity) level.
What do those who often tinker with roles think?