This is a prime example of the Issues I have with armchair engineering. While a lot of the space within the Blue polygon can be converted to guest space in some fashion, there are still operational needs that will need the be met with backstage buildings. Within your loosely drawn line you have 3 operations buildings, the multi story Animation building, a multi story parking garage, 4 dumpster locations, special events storage, Take 5 (the cast cafeteria), as well as the entirety of the Show ready Custodial department. Now it's true that all of this can be moved but only at enormous expense. If TDO does decide to go with connecting TSL to Coaster courtyard The Animation building will go or get massively remodeled, Take 5/Disney Junior, OMD and Mermaid will go. Brown derby will have to go because the kitchen is in Take 5/Disney Junior and so on. Basically we are talking about another Massive chunk of the park that would have to change Which isn't out of the realm of possibility but it would be another 3/4 of a billion dollars to do it so it's highly unlikely in the next 10-15 years. If you want to armchair engineer you would be much better off exploring the Echo lake, Indy area as TDO is already making some moves to relocate costuming as well as modifying underground utilities in the current cast parking lot.
Photo for clarity
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