Excellent solution.
Why do you need to create a custom searcher rather than just modifying the one created by the SearchAndResultsPage wizard in the UIModel folder?
The rest is pretty much standard CAB and Cabana.
Of course you are free to use Visual Studio's template export wizard
(File->Export Template...)
to create a template for your searcher views. You simply won't be able to use the Cabana wizards to set entity-specific values, so you may have more manual fixup work to be done.
300 is a lot of separate pages to create and maintain. Plus, depending on your application architecture, it can take a while just to construct them all, even if they're never shown. Have you considered other options that allow re-use of a common page for different entities?
Thanks for your contribution.
Bill Jensen
IdeaBlade