You should have the following:
All the schema documents necessary to validate (except expected)
A main "readme" document that describes how to:
Dependancies/Assumptions.
How to install.
A description of where the parts are in the distribution.
How to use the schemata.
Schema documentation.
Schema reference materials (e.g. xsddoc) generated from the schemata.
Valid examples.
License, ownership, and where to get more information.
A catalog for using the schemata.