Organ pedalboards require sitting down and so are not really what I want.
The number of keys is the real problem - I don't want to be playing a single note in one octave, I want to play my chord progression and that means I need separate buttons for the major, minor, 7th (which 7th...) for the chords that go with the song.
A medium number of keys could work out by using a custom layout for each song as many songs don't use too many chords. Similar to tuning timpani for each song.
The number of keys is the real problem - I don't want to be playing a single note in one octave, I want to play my chord progression and that means I need separate buttons for the major, minor, 7th (which 7th...) for the chords that go with the song.