Your problem reads like there's a lot of unstated constraints in your situation, like resources and procedures for distribution, management, return, collation. Too much for me. I'm looking here just at a more efficient message setup operation.
Sounds like much of your overhead irritation relates to bothway transmission of large quantities of irrelevant (even though hidden) data. Here are three lines of thought:
1. Another macro to generate 50 individual spreadsheets from your workbook.
2. Rework your base dataset in EXCEL to bare-bones tabular form, to enable mailmerge into a user-friendly WORD template. I've done this with 50 data fields into a 20-page 85-client report template, and it's a ho-hum WORD mailmerge task once you get the master doc looking pretty.
3. Take this on to include the transmission stage with the article "Integrate mail merge in Microsoft Word with Excel" at TechRepublic, at http://techrepublic.com.com/
The direct approach http://search.techrepublic.com.com/index.p...l&go=Search
might even work.
I'm afraid any of those options is a week's work, but that's why we're paid so well.