It's true that modern power devices would be more miniaturized (to a degree, they are already pretty small), as far as making it roll, I was less worried about the balance and more concerned about it no longer being able to make a spherical shape, given all the odds and ends from the new guns to the converters to make the newer power devices work with the old tech, so it either wouldn't be able to close properly, or if it did close there would be all kinds of bits sticking out.