This is an interesting thread indeed! Let me give you the most popular colors first that we see through our shop:
#1 - Grey
#2 - Tan/Beige/Cream/White
#3 - Black
But...right this moment in our shop we have an RV7 panel that is fire engine red, an RV-10 panel that is Jaguar Blue, a G900X RV-10 panel that is Raspberry Chamagne and we just shipped a Chelton RV-10 that was overlayed in Cherry wood Veneer. WE also just finished a G900X RV10 pane; that was color matched "cappacino" to the leather interior of the owner.
In the past couple of years some of the most memorable are:
Hummer Yellow, Mountain Dew Green, Big Band Blue, Red Carbon Fiber, Clear Coated Brushed Stainless, Boeing Courtalds Red, Black Carbon Fiber, Leather overlay, Wood Overlay, Rubber Truck Undercoating, Royal Blue, and a whole slew of other non-standard colors.
I no longer debate panel colors because people choose what they like best...my job is to debate avionincs and layouts!
Just thought you might be interested to know there is a veritable rainbow of choices out there.
Cheers,
Stein