the forge (building lab)

the forge 4x4 research building unlocked at th6? that allows a new level of customization via it's upgrades
these include:
town hall- requires th8
obsevertory. gives additional information when attacking a base
home guard. allows 20? troops to be stationed at the th these troops are only for defence and are placed there by you
storage. increases the ths storage capacity including de
army camp
medic camp. allow living troops to come back to the camp
more to come
defenses
entrench. turrets and towers can be part of the wall
more to come

only one of these upgrade may be purchased per building type. also looking for upgrade ideas