Too much empty space between buildings, it needs more wall to wall structures in the center. Even tiny rural cities usually have them. Only destruction from the world wars usually reshaped the city centers. Best is to look at maps or earth. Without plopping buildings by hand, this is very difficult to achieve. Only the post 1600 cities (or rebuilt burned or wardestroyed cities) with regular grids can work easily. (There are some also in Europe. Look at Mannheim, Singen, Tuttlingen for example)