Browse by...  options can act like tabs

Here's an idea of how to handle the collections pages' "browse by..."  options.    They could be a sort of internal navigation, like tabs. 

The header and the bottom section of the page would stay the same, but the items listing would change. 

Here I've only sketched the first two, but each of the browse by... options would be treated the same way. 

Edit Collection Pages (editable mockups)