Mike Lazear posted a pretty good summary of the samples included with the SDK a while back, but apparently his summary isn't available anymore.
If you search the samples, you will find that "environment", "pw_navigator" and "vaultlist" all are standalone apps.
Dean's Wiki article is pretty good, but it is possible to create and implement hooks and menus using C#. However, it does mean that you have to define the necessary structures, etc. in order to make it work. A C++ wrapper DLL isn't a bad compromise, but it isn't absolutely necessary either.