How hard (if at all possible) would it be to install some lighting in the footwells of the passenger and driver so that when the car is in eco or normal mode the lights are blue but when in sport mode they turn red.
the map lights contain separate leds for blue/red cup holder lights. you simply find the pins for these and tap the wires. run the wires to the foot well area. you'll need to run 2 sets of wires on each side. 1 each for blue/red. disconnect the OEM foot lights. add the 2 leds to each side. voila!