Hi Amy! It sounds like you're planning just as awesome a vacation for your son as you did for your daughter! What lucky kids you have!
Snow is probably not a novelty for you in Connecticut, but it's still magical to see snowflakes on Main Street USA during
Mickey's Very Merry Christmas Party! I have to admit that I'm generally not one to stake out parade and fireworks viewing spots in advance, but thankfully, I'm usually at the Christmas Party with some of my fellow Dads here on the Panel who are experts at finding the perfect spot! A few years ago,
Bernie showed me that the ideal place to watch Holiday Wishes is in the center of Main Street between Crystal Palace and Cinderella's Castle. You'll find an area of the street that's slightly higher there and it offers a great view of the fireworks on both sides of the Castle. After the fireworks, it's easy to just walk forward to catch the show in front of the Castle, which is usually scheduled to begin shortly after Wishes ends. Disney Dad
Marc discovered the best parade viewing spot ever: at the end of Main Street (near the entrance) under the giant Christmas tree. The floats head directly toward you, so the view is awesome!
Be sure, of course, to sample the free cookies and hot cocoa, and to take time to get photos with the characters decked out in their holiday attire. (Of course, it's fun for you to wear holiday attire too -- you can buy cute Disney holiday hats!) If your son is able to stay up later, you'll find the lines for the characters and the crowds at the parade are smaller later in the evening.
I'm so happy to hear from you again Amy! Keep me updated on your December vacation plans, and visit me here again if I can help!