Limit time an account can be played via holiday replacement
I´ve noticed that many accounts are played only via holiday replacement. They´re leveled up, placed at POIs and are only used by trolls in center to block other allies forever. It just takes too much resources to attack fully leveled up bases again and again, without any costs for the guys who play them. Why not limit the time a holiday replacement is valid? It should be used for a common holiday, maybe max for 4 weeks. Since nothing is done to give other allies (which spend a lot of money too) a chance to hit the fort when some trolls sit in center at least let time work for them. When more and more player leave the world their accounts have to stay dead when shot.