I think the future is modular building!
Instead of giving completely new firestation, hospital, airport, policestation... every 3 or 4 years, only new modules could be made. For example we got a firestation this year, next year we could get a add-on: A garage, then a new module: sleeping quaters and so on. The same thing could be done with all of the sets. The original sets shoul be around 50