You can look for color changes in Zi Ling, such as using beige Zi Ling. Anything in brown will do. It's harmonious and beautiful.
As for the seal, on the red paper, you should first cover the seal on the white rice paper, and then ask the painter to mount it in a suitable position according to the calligrapher's requirements.
A framed work can be hung on the shaft, or you can buy a picture frame to decorate it.