I was Hoping that the Seven Deadly Sins Would Serve a Purpose
Like manipulating people to commit sin, or even play on existing sin, but we didn't really get any of that in the film.
Apart from a throwaway line where Doctor Sivana commands 'Greed' to attack his 'greedy' father, and the end where Shazam teases 'Envy' to escape Sivana by mocking him, the Sins could easily have been any generic monsters. It's not as if they targeted people in accordance to their traits. They went after any and everyone.
If they do a sequel, I hope they bring back the Sins and give them a less generic role.