Don't do streetcars, they suck. Don't get me wrong, I love me some trams, but new streetcars in the U.S. are almost always vulnerable to traffic and traffic lights. They also tend to be built in short loops around gentrified downtowns. They are real estate speculation tools and not mass transit.

Light rail is good, if it's a smaller city that's a good idea.

Subways are worth it in dense areas but only if they're automated. Automated subways are a sight to behold. They can keep running late into the night at high frequencies too.