I do think that the 1/4" jack/barrel style power adapter paradigm is seriously wrung out. Time for something more useful. I present you: neodymium! The Snapjack cable uses a neo magnet to hold cable and 1/4" jack together. Make a pedal enclosure (or just a bass plate) with neo magnets on each side-double concentric rings or 4 individual magnets. Each pedal would need jacks if it's the last pedal in the line, or if you want to power it separately, so those'd go on top. The pedals would simply snap together, held by the neo magnets, and supply power and signal to the next pedal in line. Using the super small pedals you could have a pedalboard with everything on it on a PT2 with space left over!