For several years I've been advocating that the DC feature movies should be more like the animated ones. Make continuity completely optional between films and just mine all the classic stories you can find. Run different versions of the characters with different tones, art styles, and world building depending on the needs of the story. Above all, just focus on making each movie as good as it can be instead of worrying about connecting it to a dozen different characters that are being forced into the same style as your main characters. If that means having two different actors playing Batman at the same time, cool. They've been branching out a bit more in that direction (Joker most notably), but they've still got a ways to go before they just focus on making one good movie at a time.
I mean, I liked Man of Steel. It wasn't perfect, but I'm glad I saw that version of the character. But DC cinema never had a chance when they decided to structure the entire world around it.
I feel like there's been some level of continuity (at least, in this set of movies: https://en.wikipedia.org/wiki/DC_Animated_Movie_Universe), while most are standalone stories, a few of the side characters show growth and the timeline remains consistent.