PS My non-expert opinion is there is too much copy on the back of the card. People's attention span is shorter than ever before. (This from someone who has been correctly accused many times of undue verbosity!) I HIGHLY recommend this 30 year old book that is more apropos than ever:
PS Plus Yeadon wrote most of it and he gets paid by the word. I on the other hand get paid for every time I can put www.SFS.JonDon.com up on the web. Oops- did it again!