Interesting post.
My guess is that this new area will be built on the set-down area/taxi rank, essentially connecting Check-In A&B on the ground floor level. Should make passenger flow a lot more sensible.
Looking at terminal maps, the ground floor is relatively straight-forward to do, with just domestic arrivals to consider, and also creates a lot of new space. On the first floor a lot of reconfiguration would be needed, I suppose the "staff only" area could be moved downstairs into the space created down there. The burger king/yates, etc would become airside and the "void overlooking Hall A" could be filled in to create a large, centralised, waiting lounge, the gates on the ground floor would be lost, however, unless a staircase were to be built connecting to the first floor. A fairly major remodeling should result in a lot more pax being able to progress through the terminal before an extension is needed. At the end of the day, its the security, passenger flow and gate waiting areas that are the biggest 3 problems, there is enough space if it were used correctly.
Brian.