The Brooklyn Bridge is a hybrid cable stayed/ suspension bridge, it is about 1.13 miles in length, it has a neo-Gothic design, the arches are pointed, it has open trusses, the cables have a diagonal design, it is tan and silver in color (originally it is said the color was red) and the towers are made of stone. Most of the pictures depict the bridge as part of the city skyline, rarely is it pictured by itself.
The Golden Gate Bridge is a suspension bridge, it is about 1.7 miles in length, it has a modernist design, the arches are square, the cables are straight up and down and it is International orange in color. Most of the pictures only show the bridge itself. There are a couple of pictures that show the city in the far background.
To me the differences in the way the bridges were built has to do with the change in time, they were built 50 years apart. When the Brooklyn Bridge was being built we had more of a European architectural style and bridges of the length and design was still fairly new. The materials that would have been available during this time would have been in line with the times. When the Golden Gate Bridge was built the architectural style was more modernist and bridge design had become much more advanced due to rapidly changing technology. Due to this the materials that would have been available would have been stronger and more advanced.
I think the fact that these bridges are still standing and have only needed renovated and reinforced shows the type of quality that was expected and the thought of the future that was seen. If you look at both New York City and San Francisco you can see that many of the designs of their cities have stood the test of time. They seemed to value quality work and planning and value the image the city holds for the rest of the world.