His torso was the biggest section of his body. It wouldn’t have his heart, lungs or any of that, because he didn’t have a circulatory system. More likely, it contained his brain, his sensory organs/system, and whatever mechanism he was using to remotely control his arms, legs, hands and feet.
That does make a lot of sense. Gotta have a little extra space for those.
And didn’t his torso have a little window on the front? (Which I guess has to regularly survive Shatterbird, so it’s probably not made of normal glass.) That might be the weakest point available, though probably not a weak point.
It’s also worth noting that the torso can split in two. I wonder if he keeps the halves of his brain separate?
Unless he didn’t want to put all his items in one basket. It was easily possible for some of that stuff to be in his thighs and forearms.
His brain definitely needs to be connected to the remote control stuff, but maybe it’s remotely connected to the main center for that?