is_system_list not set to system lists in base profile (base.xml)
The documentation says that there are 33 system lists that must be defined. It also says that the attribute system (= intrinsic is_system_list) must have the value "1" if it is a system list.
However, base.xml does not mark a single one of the 43 lists defined here as a system list. This should be corrected. We should also explore modifying editing behavior for system lists:
1. Do not allow system lists to be deleted
2. Show a warning while editing a system list that changes may alter system functionality.
3. Add ability to only show system lists in the lists & vocabularies editor and/or segregate system lists from content (non-system) lists.