-Since Downs is one of the safest prospects, I would consider a small trade up to land him if he comes in reach. Pick 93 would the most I would offer or maybe a swap of draft slots. Perhaps 9,30 and a day 3 pick for 12 and 20.
-Bain might not be the ideal fit, along with the physical traits you look for, but he is still a top 3 pass rusher in this class. At 12, you take him and adjust the defense around his skillset. Too good to pass for a lesser prospect.
-Plan certainly looks like building a stout run defense and playing that shell coverage. CP's biggest thing will be about post snap disguise. To be able to run this scheme, he needs that hybrid nickel to act as another run defender due to that light box. Don't rule out either Scott or Stukes higher then we expect.