i would seriously consider doing major reduction and some training with it in the ground it looks to be quite a large specimen and will have a very large root structure. reducing the foiliage will help when trying to form a movable rootball when it is potted after a couple/3 years
Agreed. The yins are the last of your challenges with this tree. Prepare the tree for 2 years to get it to move (Reduction of foliage, and creating your roots close to the trunk). Then move to a container, and just let is grow in the container for a full year. Then you can start thinking about the styling, and therefor the Yin.
The reason why I would not do anything on deadwood now: This is a major transplant, with serious risk of large parts of the tree dying, and the possibility of the tree breaking bud on other places. Any design you do not might be impossible in 3 years.