My personal opinion: I think the whole "universe" thing doesn't really add much to any individual movie, and often takes away from them.
Just make entertaining films... self contained.. if characters continue on, have some continuity, but I really don't care if some other character shows up in a film, or they have a big "team up" film ala Avengers/Justice League personally. At best it's.. "kinda neat" to me how the films connect.. but people calling the MCU "brilliant" for it are weird to me.. it's called... a storyboard.. and these stories have largely already been written for them lol
It's far more interesting what they did with Joker.. and this movie sounds far more interesting than another Cavil Superman movie.