Second step after Man of Steel: a sequel. In this movie, however, it is not a solo film, but a team up of Superman and Batman. We all know the origin, this is just a confirmation he exists. Let this movie serve as an introduction to Batman, as a builder of Batman's and Superman's relationship. Then, in an after credits scene introduce Martian Manhunter in a Nick Fury way. What makes this movie special is that its a partnership/team up with 2 extremely powerful heros; something the MCU has yet to have.
In that same year as well have a WW film. The film would introduce for the first time on screen WW. During the film you can have a Barry Allen cameo as a man on Earth that tries to hit on WW, who then takes off in her invisible plain, which would then result in Barry chasing after her, revealing his powers. In the after credits then there can be a quick cameo by Aquaman. I can't figure out true details on this however...
Finally, keep Green Lantern in continuity and have him make a "Bruce Banner" return in JLA the movie. From there you can go with solo films.
Thanks everyone for reading, state your thoughts below!