When in doubt, try the opposite.
Traditionally, one would bevel the accent pieces and leave the background uneventful. Trying the opposite, I beveled the background and used rippled stained glass for the accents.
The combination resulted in a soft, glowing window, where the light played a crucial role in enhancing the beauty of the glass as it shimmers off the background and the foreground.
This subtle uniqueness is what makes art glass such a beautiful architectural accent.