Hey hey hey! I'm the guy who made the Mettaton Steel kick calc. I'm not really gonna ask about that yet or comment on the rest of the thread just yet (although I am curious because it doesn't sound like a recalc is out of the question, but enough of that for now). I skimmed through the thread and saw that the soul width is 15 centimeters yeah? Papyrus contains all of his attacks in his box also yeah? Well I double checked to see what Papyrus' bone measurements would look like,
here's what I got:
Soul: 49.01 pixels = 15 cm
Big Bone height: 709 pixels = 2.15 meters
Little Bone height: 143 pixels = 43.77 cm
Big bone width: 58 pixels = 17.75 cm
Little bone width: 14 pixels = 4.28 cm
Sorry if it seems super blurry but I'm ngl that box's width doesn't even look longer than Frisk's height. It's supposed to contain 402 bones INCLUDING the massive bone? I'm not calculating the volume right now but I'm sure if you did volume calcs here, the total volume of the box would still seem hilariously high no? My point is that if this is the issue, is 15 centimeters for the soul also kinda not high? I suppose if you assume that the game is extremely meta and the battle box stuff is canon like it seems to be in Deltarune, the attacks would vary in size based on combat which would make sense of the legs and Toriel hands stuff.