As previously mentioned, the proposed expansion is marked with the blue tape. When you have limited space like this, the allotted area is mandated and track/buildings will be adjusted to fit.
I will probably use this as a switching annex as my layout has three loops with no switching possibilities. Also, my newest engines have Bluetooth control and would be easy to switch with.
I will hold back on the hinged lift bridge for now and contemplate its advantages and disadvantages.
The closeup illustrates the place where the Ross 042 switch will be used.
John