• A grassy town square, like a park with some kind of outdoor casual venue for speeches, music, gatherings and other uses. This should also have a guide map to all the builds, even while they are under construction.
• A copy of the polling location and possbly poll worker training or use this for virtual elections
• A code house with municipal code information showing instructions on a real structure 
• The paramedic training simulator - See example video
• A Conference room - See example video
• An auditorium
• A meeting room that could be used for virtual public meetings
• An ECC simulator of a CAD workstation
• Billboard advertising to other government builds
• Freebie store of clothes and other basics
• Noob welcome center
• Police/Public Safety building and include a CSI simulator
• Library resource of Web2.0 policy and practice, open data sources, shared resources
• Sandbox for new builds and member practice

Add your ideas in the comments below.