Hi,
Not sure if this has already been suggested, but here it goes.
Within the permissions area, for both "trigger a workflow action" and "modify the workitem" it would be useful to organize their children per WI type.

For workflow actions: it would be more friendly if I have an additional level in the hierarchy to expand the WI type and then list the associated actions within its workflow (today all the actions are shown together and it's more difficult to find what you want).

For WI modification, again: instead of having the complete list of attributes available in my RTC proj area, it would be more useful to have them classified by WI type. Today it is difficult to remember which attribute belongs to each WI type.

Hope this helps.
Claudia