The CH Products line of joysticks/yokes when used with the CH Control Manager software already have this feature...that's what the little green/red/yellow led indicators on the stick are for...to indicate which program mode you are using.
Each button or hat on each device can be programmed with up to 3 different functions, and each assignment fully supports all available keyboard modifiers...Shift/Alt/Ctrl etc.
I have no personal experience, but I believe the high-end sticks from Saitek and Thrustmaster have something similar, so why do we need to change the game?
Aces High 2 already has the best stick-mapping routines and joystick support available to any Flight-sim that I have ever used. The options provided allow practically anything that you could think to do or want to accomplish, and allow mixing the game's own routines with those of the joystick manufacturers software (CH Control Manager).
CptA