I would probably go down to 2 per 3c section. You could replace them with more Dimir, Rakdos, Golgari or Orzhov cards.
https://cubecobra.com/cube/deck/5fda32ea88d2130fa2878e56
I have drafted your cube to check how wordy it is (and to generally check it out, I'm not sure if I even have...