How can I assign different preference sets to different levels?
While you cannot assign a preference set to another preference set, you can assign different preference sets to different levels. For example, if you have PREFERENCE SET 1 that you assign to MODULE1, all module components, items, item groups, and constraint usages under MODULE1 will inherit that preference set. If you want to apply PREFERENCE SET 2 to that module as well, you could attach it to all module components for that module. In effect, you would have two active preference sets governed by the precedence and inheritance rules.