Have you ever done any real print work? How is anything going to print onto the letter paper once you have it printed up? The design itself is impressive but the letterhead/letter page is really going to kill any reason to spend money on this.
Fix the letter. Remember the way these usually work is people have a professional printer print these out by the hundreds or thousands and then print on top of them with the home/office printer.
There aren’t any printers that will print white ink onto this once it’s been printed.
Nice work though, you just need a little more experience with print.

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