Hi Karl,
It seems that an SCArrayOfObjectsModel is a perfect fit for you. For an example on how to have STV automatically generate the sections for you, please check the Core Data sample application, under the "People" tab.
On a side note, please note that you extend the definition of dictionaries using an SCDictionaryDefinition, as opposed to an SCClassDefinition for your normal classes. For an example of this, please check the dictionary editor tab in the Samples App.