And there is barely any Justice League in it. Honestly if they had left the resurrection of Superman for its own movie it would have worked a lot better. Here the opposite is true, combining both the death and return into one long movie works a lot better.
I honestly can't imagine the Death part working on its own, barely anything happens before the end besides drama that we have already seen the conclusion to a hundred times, and the second part on its own would surely be far too convoluted. So we'll done to DC for making this narrative into one part. It just makes sense.
Overall this arc is a complete film, although they probably could have shaved down some of the conversations, especially with Lois Lane, who seems to be there to pad out both separate movies, but most of her stuff doesn't need to be here when combined. Good story, drags a bit.