Lesson learned: You should never put this many layers of cardstock together, and try to mail them, because even though it may NOT be too heavy, the darn thing is so stiff that the geniusus at the post office will tell you they can't "machine" them, whatever that means, and will give you much grief.
This is the final product - note the printed insert was supposed to have a gold foil border, instead of black, but it didn't work out in the printing stage, unfortunately. But we did tie the gold in (50th anniversary - gold - get it?) with the gold foil-lined envelopes, and the gold metallic detail on the ribbon tied around each pocket.
Hooray for being finished!