Taiko buttons are already shown... just look at the drum.
There is one thing in CtB that cannot be seen from the character, which is jamming, where both movement keys are held down at the same time (this can be an easier way to stop the character than releasing, because it's a positive input instead of a negative)... note that if the dash key is also being used at the time, you can tell if there was a jam. So there might be a call for it there.
There is one thing in CtB that cannot be seen from the character, which is jamming, where both movement keys are held down at the same time (this can be an easier way to stop the character than releasing, because it's a positive input instead of a negative)... note that if the dash key is also being used at the time, you can tell if there was a jam. So there might be a call for it there.