As a self-proclaimed train geek I understand your plan, you want to ride on a specific train, and not seeking most convenient way between Narita Airport and Maihama. I think you hit key trains, Narita Express, Keisei SkyLiner, and Shinkansen.
As other have mentioned transfer at Tokyo station between Narita Express and Keio Line, and Ueno station between JR and Keisei line can be time consuming due to distance of transfer at those stations. Both are large station and if you make one wrong turn then you can easily waste 5-10 minutes.
As for double decker Shinkansen, look for Shinkansen train with “Max” such as Max Tanigawa and Max Toki on Joetsu Shinkansen are run by double decker Shinkansen trains. Obviously, upper deck seats are more popular than lower deck seats. I sat on lower deck seats and at a station eye level is people’s foot on a platform. When train is running, the view form double deck is next track and wall on Shinkansen track prevent any further view. Some people say watching track going by that fast is not pleasant, some say it make them nauseous.