One potential issue might be that if you are trying to manage the content of the components of documents, you'll need to keep track of page numbers. A way to mitigate this issue will be to think of an entire folder as a contract and keep each piece that might need to be updated as a separate document inside that folder. Use metadata to uniquely identify each piece that makes up a contract. Then you should be able to easily make changes to the various parts without needing to worry about it's relationship with other parts. Then if you need to, you can have Workflow build you a combined version.

Does that help?