2. Setting The Action During The Day
Aside from a few scenes in The Dark Knight Rises, Batman is a night owl, and conducts the vast majority of his business at night, as suits the character and the aesthetic of the films. Superman, meanwhile, largely fends off evil regardless of the time of day, and as we saw in Man of Steel, most of the action took place in broad daylight. The thing is, who wants to see Batman fighting during the day? Short of a heightened aesthetic as in TDKR - where snow was falling on Gotham - Batman needs to fight at night, yet this is not something that Superman typically does. Perhaps it sounds like a nitpick, but this just further exemplifies how different the approaches to the two characters are, and how potentially calamitous bringing them together can be in even the most simple of ways.