Possibility to set building options when building is under construction

Wishlist: give the player the ability to change the settings of a new building directly from the construction site. So when one starts making a building, he could click on a window like "building preview" and see how the finished building would be. From there he could choose some settings, and they would immediately be applied to the new building. So one could start a sentry and tell it it only must have one soldier inside, or he could start a tavern and tell it to not use bread. Maybe one could even tell the building to upgrade immediately once it's finished, and then he can choose the settings of the upgraded building.