I am sure that the most important measure at this moment is to improve the public transportation, because it is working and a change would be much more fast about it than about any other. In Brazil, the cars and buses were the focus of our ancient government since the push to the industrialization in the mandate by Vargas (a brazilian former president), when train was rejected as the main mean of transportation. So, Brazil has had a poor public system, because the buses don't be a priority, unfortunately, I guess to our goverment the public system is just a mean of transportation to poor people in order to it works a lot, instead of thinking about a mean that were for all people, rich and poor. If Brazil had a good service by train and buses, our country would be much better, the quality of our lives would become better and the largest cities would be more enjoyable. Maybe penty of accidents would be avoid and our healthy would be improved.
I don't see a possible change in the next years, but I am convicted these will be a fact someday, else some cities of Brazil will enter in a colapse.