Adding a timer to placing structures would be a nice feature. For example placing down a door should take a little bit of time to fasten it to the door frame. The larger the structure, the more time it should take to place. Foundations for example could take 120 seconds to place down.
While placing a structure the player is unable to move and can cancel at anytime or be interrupted by damage, but if done so will break the structure being placed. Plopping down structures as it is now seems somewhat shallow.