Adding more blue: Presently - the window design has three strings of five pastel colored turquoise glass gems. To create more of an emphasis of blue in this design, three strings of five darker turquoise gems can be soldered in. Turquoise/teal small glass beads could also be considered. I taped a few of these glass gems so you could see the comparison in colors.
In both of these photos you can see the solder lines stained in the copper patina.