To be fair, the dictionary order is out of synch, too (although not as much--ㅊ is first among the aspirates whereas ㅈ is last among the regular consonants). Still, if you're going to line up all the consonants to one side, why not order them according to place of articulation? Especially when their forms encode it! If it had been given to me to do, I would've had plain consonants in the middle, aspirates above, and nasals below.