Changes

Its recommended (if you are playing sandbox mode) to lay out your streetcar roads first, and weave it through the core and important locations of your city. Place your street car stops at culture,gambling,etc. locations when designing your new city. When your city gets developed enough and populate, your sims will start to beg heavily for streetcars. Thats why you lay these roads out first. Plus you re-leaf relieve a lot of traffic problems in your city and makes your sims super happy.