Despite the apparent concerns at Warner Bros about Batman v Superman's overly dark tone (and how that impacted the final Justice League cut), it seems that Zack Snyder was still shooting for something a lot darker than what we actually got. You know, despite how loudly everyone involved was talking about Snyder always intending to change the tone for the ensemble movie.
According to Kevin Smith, Snyder's vision was indeed the one teased by extensive (now deleted) leaks on Reddit/DCEULeaks. The latest edition of Smith's Fatman On Batman show actually features confirmation that the version screened to test audiences earlier in the year were the same as those leaks.
That version had more Apokolips and Darkseid, with the agenda to set up a sequel in which the latter would take centre-stage and the original ending would have set that up overtly. It was ultimately reshot to remove the scene of Steppenwolf returning home and being killed for his failure in order to make Justice League completely stand-alone.
We would also have seen more of thebackstories of The Flash, Aquaman and Cyborg, more of a close tie to Man Of Steel and Batman v Superman (including referencing the Codex, which would have made more sense to Supes' resurrection) and a more serious tone to Batman.
Warner Bros apparently screened numerous versions of the film to see which worked best, and clearly Whedon's lighter tone and comedy landed better, which was fatal for the darker elements.
This will presumably do nothing to dampen the stubborn desire from some Snyder fans to see the Snyder Cut that doesn't exist (at least not in a completed form, anyway). But Warner Bros could well make a bit more money if they feed that obsession...