TOEFL essay "building shoping centers in my neighborhood"

I have never received proper instructions on how to write a TOEFL essay, and I really need advice. Even if the advice might seem very basic, there is a high probability that I don't know that piece of information, so any kind of suggestion is extremely appreciated.

So, a few questions:
1. I've heard that a 5-paragraph structure should be implemented, but I decided to put a contradictory opinion in between the 1st and 2nd body. Was this a bad idea?

2. I put very little time (like the last 2 minutes) to review, and I decided to put more weight on writing as much as possible. Is this a bad strategy?

3. Is it true that the more you write, the better it is?

4. I find it hard to come up with an appealing introduction and conclusion. What are some strategies?

Prompt:
It has recently been announced that a large shopping center may be built in your neighborhood. Do you support or oppose this plan? Why? Use specific reasons and details to support your answer.

The essay:
While people who liked the neighborhood for its quiet and peaceful atmosphere might strongly disagree to build a shopping center, I am a supporter for the idea.

Firstly, it creates competition for local stores previously without it. Before having a shopping center, a local store might have been able to have high pricings and still be able to keep customers, due to having little or nor competition. However, by having a shopping center in the neighborhood, these stores will have to lower their pricings in order to compete with the new stores in the shopping centers. Competition can improve service as well as price. Local restaurants will have not just one, but at least three rivals when a shopping mall is built in the same area. Then providing bad service would be out of the question. They may have been able to make profits before, because the residents had no choice but to go to the restaurant if they wanted to eat out, but that will not be the case once they have competition.

However, this argument is double-sided. While it can be seen as a good thing from the customers to have competition among stores, it can be devastating news for the stores. If the service and price offered at the stores in the shopping center were equal to that of the local stores, or even slightly worse, I think people will most likely go to the former. After all, compared to the stores they have seen all their life, the stores in the shopping center are new, shiny, and going to the shopping center might be an exciting experience in itself. So, there is the risk of having local stores shutting down due to loss of customers.

As for the second reason why having a shopping center is good, it can be a place to go at weekends. I often go to a movie theater in a shopping center at weekends, and I know it can be quite fun to spend time at a shopping center. Why? One reason has to do with the fact that I like busy places. Growing up in Tokyo, I am not accustomed to places where there are very few people, and I am more comfortable where there's constant bustling around me. Another thing is that there are so many shops to look around. There are clothing stores, toy stores, CD stores, bookstores, and there are usually more than one shop for each kind. And whenever you get hungry from all that looking around, you can always stop for a sandwich or coffee.

And lastly, it profits the neighborhood economically. Building a shopping center means there will be shops making money, which means more tax income. And more tax income means, hopefully, a better life fore the people living in that area. For example, a new facility can be built, such as a pool or a library. Recently, tuition in state colleges has gone up in California because of the state's bad economy. If a state had sufficient income, on the other hand, they would be able to provide cheaper tuition.

Therefore, although it is not without consequences, I support the idea of building a shopping center in my neighborhood.

Thank you.

If you really want to know, I got a 27 out of 30 on my TOEFL iBT (It was not a 30 because I didnt had enough time to correct a couple of spelling errors), so this is what I did:

First of all, dont count how many paragraphs you use, it is better to know what will you put inside of these paragraphs. My technique was to put an introduction first, here you introduce your position on the subject, and what you are going to talk about on the next paragraphs. In the middle paragraphs, you put the pros and cons of each thing, and why would you consider it positive or negative, depending of what position you have on the subject, and finally, in the conclusion, you will resume all of the previous ideas so you can clearly present why you chose that position in this subject.

Second, try to use the most varied and specific words you may find. Instead of using "get" use "acquire", use "vast" instead of "large" and so on.

It is also helpful to think about how you are structuring your essay before writing it. Do so when you take the test, and after you are done writing it, re-read it for mistakes, and if you can for replacing the simple words and repeated words for more specific and varied words, like I suggested before. I am not sure, but I think I wrote about 4 paragraphs, so mainly, in order for you to write more, you need to administrate your time properly, otherwise you will run out if time, and that happens really often.

These are all the suggestions ive got, good luck on your test!

Thank you for the help!

If there's anyone reading this thread, essay editing would also be appreciated.