I recently started working on a new project using the DXA. One of the site types was a rebuild; using an existing content model rather than creating schemas from scratch. Part of the DXA philosophy is to enable MVC developers to use simple view models which hide the complexity of the underlying domain (CM) model. This article shows some tricks you can use to do help take this approach. Its based on the .NET implementation but the same concepts should apply to the Java version.
DXA Model Mapping Cheatsheet
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