Since a mainstay is required when standing guitar playing, basically foot controller of guitarists will be operated with one foot only (right food for right-handers, left foot for left-handers). Perhaps this helps to reflect on the method of control of the buttons.
Another idea for the Tap button:
Is the Tap button actually really needed? I can define with my FCB the tempo of the delay by repeatedly pressing the corresponding soundselection button in time, which is very convenient for me. So I do not always need more buttons use to select the tempo of the delay, in addition there is also the Beat Detection. If this were possible also in KFC, the now planned Tap button could also assign a freely selectable function / scenario?