One of the biggest issues I had with Whedon's version of Justice League is that the Justice League never felt like a team. They were six superheroes that were working in proximity versus being a true team. With the Snyder cut, we get to see their motivations and reasonings behind being wary about joining Batman on his quest to create the team. We know why they ultimately want to save the world and they no longer feel as if they are a one-note imitation of their Marvel counterparts.
In this version, Batman and Wonder Woman's flirtation is subtle rather than out of character. Even the jokes that do make it into Snyder's version feel appropriate rather than a clumsy attempt at shifting the gritty tone of the film. Whedon's version felt focussed on the CGI, aesthetics, and what the characters could do, not their motivations for doing things. Unlike Whedon's version, I didn't leave the Snyder cut confused as to what just happened. I left wanting more of the Justice League working together.