There's no way from a programming standpoint to track it as I see it. If you make something like how many decorations have been used to build the city for:
1) One user could put all his decorations in one place like on top of the arena and that would look ugly but it still gets you money.
2) There is no rational way of determining which city is "well build" and which one is not because beauty is informal what is beautiful to me can be ugly to you.
Basically, verification of this feature is impossible to implement.
Founded in S7 | Returned in S30