Instead of building my city, I'm forced to tear part of it down repeatedly

I have the same opinion. Rewards in the weekly and other temporarely events should be achievable, but are not since the last update, only if you do so it as described above by tearing down parts of the city. Next to that is it impossible to plan your progress as the differrent levels of the week events are not visible and these levels are changing every week, esp. since previous update. Why does EA/SC not give these information?