Writing Feedback / 'People to be realistic or optimistic?' - grade my SAT essay [4]

Assignment: Is it better for people to be realistic or optimistic?
Essay:
Should we be optimistic or realistic? Obviously, optimistic people always expect good outcomes and happy endings, whereas realistic ones view life as it is with its good and bad. As far as i am concerned, realistic people are always discouraged with their counterparts' experiences, and thus they never contribute significantly to the society. History and science abound with examples of characters who procured high statuses in their careers solely with optimism. One example is Wilma Rudolph. Prematurely born and having a left-leg paralysis since young age, Wilma Rudolph is a model example of optimism and buoyancy. After removing the metal leg braces she had been dependent on, Wilma developed a rhythmic walk by the age of thirteen, which stunned all doctors of the time. Because she believed favorable outcomes will always occur, she decided to be a runner although she apparently had no facilities to do so. That prominent character was the last in each and every race for many years that everyone asked her to quit. Finally, she started winning a race after another until she became a famous runner with three Olympic gold medals. Had she been realistic, she would not have tried to run or even walk, simply because no one similarly situated did. Another instance I can bolster my point of view with is Thomas Edison. An American businessman and creator of many crucial inventions, Edison did not invent the light bulb easily. Failing over 2000 times to get his light bulb to work, Thomas Edison did not give up until it really worked. Ironically, when asked by a reporter about how he felt after failing so many times, he answered "I had never failed; I invented the light bulb in a 2000-step process." Has he been realistic, he would have stopped after the first few failures since "logically" this project was never expected to come to life. In the end, favorable expectations form the only route to success and innovation. All of the things we take for granted today could have never been there if their inventors were realistic. One should believe that sky is his or her only limit and that we are created to degrade impossible ideas to become normal. Finally, do you prefer realistic or optimistic people?