Took another stab at this technique and I am even happier with the result. This time I used the actual magazine page for the transfer instead of a copy of the image (this is a Southern Living floral arrangement, btw). Removing the magazine page from the packing tape takes much less time than regular cardstock! However, it did leave some faint lines along the packing tape edges. I don't mind the lines, it just adds to the aged look.
My friend Dr. Craftenstein recommended sanding the transfer lightly to remove some of the shine and that was exactly what was needed. Thanks Dr. C!
I made another one of my paper bag 'envelopes'. Unfortunately, I learned that the United States Postal service machines will sometimes grab onto an embellishment and then proceed to mangle the envelope. So, I had been wrapping up embellished cards with paper before mailing. Now, I slip the card into this little paper bag. Opening up my cards is now like the opening sequence of Get Smart.