Balconies are a great amenity for urban apartments. They allow the residents to get immediate fresh air without having to go down to the courtyard or the street. They also give a building legibility; balconies say "people live here!" A bay of balconies can also break up a long facade and give it some rhythm and visual interest.
However, at the ground floor this amenity is sometimes treated as a fenced-in private patio. While this is fine within a courtyard, I strongly recommend against this adjacent to a street. The patios, which sometimes have high fences right at the back of the sidewalk, create a tunnel effect which makes the street feel very unfriendly.