Photos! The Central Park Hoodie blocked to the right size without any problems, and now I've finally photographed the evidence, I can sew it up.
As you can see, the front pieces are in no way too small, or smaller than the back. They just look tiny when they are still on the needles.
I decided to knit the button bands separately, so I could block them to the right length before attaching them.
Even the button holes are being blocked! I did the classic cast-off 2/cast-on 2 button holes and of course they looked classically ugly. So when the button bands were wet, I found some egg-shaped glass beads and wedged one into each button hole, to block it into a more attractive shape. They are now perfectly round.
I dried this sweater with the hood already on. I pinned out the front and back of the wet sweater, then I arranged the hood facing to the back and left it until it was dry, and then I flipped the hood so it faced the front, and dried the other side. It worked out okay. You can see how I've put paper and whatnot inside the hood to keep it from collapsing on itself while it was still wet.
Yay! All blocked! Now to ruin it by sewing it up.