Hello,
I work on Broadway shows, and I have a document for each production I work on to keep track of tasks. This means that I have 6 or 7 documents for different shows all based on a single template.
Here is the major suggestion: Make each document an instance of the template with local data. That means that modifications made to the template would roll out automatically to each document.
That would prevent the labor intensive task of making a change to my template AND each of my documents. No one has time for that!