FWIW the Kenren frontispiece is the same in both editions of Gaiden 1, just has thinner lines in the new version. The colour pages that start the book have more colour in them- Nataku appears against a blood red background- and a tendency to the browns she's shown so much love of in her art books. Goujun now looks like yellow ivory, Kanzeon is yellow-brown rather than peach. I'm not quite the fan of it myself.
Have my new Gaidens courtesy of