Not that I'm aware of - nor on the 7D, even with it's greater level of possible customization of the controls. Using the custom modes seems to be the best solution. You could add Camera User Setting to My Menu (with Display from My Menu enabled) to make it a little faster to re-register the changes, and also set a longer time delay to standby (to avoid the frustration of changing a setting, waiting for a shot, then waking up your camera to the reverted settings).