Don't do it ...it's done!

Did you want to make -

- A graphical treeview-based editor/VS addin for examining and editing Open XML Package files

- A custom tool window/VS addin that displays all re-usable built-in Office Ribbon IDs.

- A set of classes for coordinating multiple instances of Ribbon, custom task pane, and custom form region objects.

- A set of C# classes for handling parameterized properties and optional/named parameters, as well as for LINQ-enabling Office collection objects.

And some more interesting things that you felt were missing? Well, No need to spend time on it :) It's already done.

You can download it from here. Please check andrew's blog for more details.

Additional resources