these extras would be:
Military HQ:better military units and more health to other attack units
Resource lab:makes all resource buildings produce more resources and ultimate recource generator unlocked
Spotter tower:all radar and jammers ranges increased and statellite unlocked
something dealing with defenses: increases range of guns and allows an extremely powerful weapon.
if you were to build one of these buildings, the others would be blacked out. and if you were to lose your selected building due to sharing, attack, etc. everything it allowed you to build would be destroyed. (to stop cheaters

Now, could Lua do this?