I don't think it's a good idea. A preset is a single state that needs to be recalled on various occasions and adding another abstraction layer on top of that will lead to issues and regression problems pretty soon and the possible use cases are way too broad to be covered with a "hardcoded solution".
You can achieve this kind of customized loading / saving with the pre / post user preset callback where you could remove eg. all mixer gain values if the user chooses to do so.