If you like your superhero films stuffed to the gills with perfectly powered protagonists, then Captain America: Civil War is the safer bet out of this year's superhero team-up films. Surprisingly, with as many heroes as there were present in the Captain's third box-office outing, there were almost two more added to the roster: Ant-Man's Hank Pym, and the Janet Van Dyne variant of The Wasp.
Now we'd previously heard about the original plans to include Evangaline Lilly's heroic debut in Captain America: Civil War, but as far as we can tell this is the first we've heard of Michael Douglas' Hank Pym being in any draft of the film. And as far as writers Stephen McFeely and Christopher Markus were concerned, any talk of Pym's inclusion was squashed rather early, and for one key reason stated below in their interview with Mashable:
[Hank Pym] wasn't as helpful as he needed to be.
As for Janet Van Dyne's exclusion from Captain America: Civil War, Markus and McFeely echoed the sentiments of Marvel Cinematic Universe big wig Kevin Feige, stating that introducing Janet's Wasp is a moment best handled in her own film, and not as a throwaway moment in a team-up flick. While the introductions of both Black Panther and Spider-Man were both handled perfectly, despite being included in an already stacked plot, they were also integral to the plot of Captain America: Civil War. Presumably, Janet and Hank's roles would have been tied to Scott Lang's presence in the film, and seeing as Ant-Man himself isn't in the film for all that long, it would have been a waste of a good introduction.
One of the key reasons to include any character in your story, be it Captain America: Civil War or Batman v Superman: Dawn of Justice, is to have the justification for including those characters. Perhaps if Zack Snyder had the advice of Stephen McFeely and Christopher Markus in his ears during the production of his DC Comics team-up film, there might have been more of a cohesive flow in the plot. After all, while Batman v Superman: Dawn of Justice had a main plot involving Batman, Superman, Wonder Woman, the three other Justice League members that appeared (The Flash, Aquaman, and Cyborg,) really didn't play a part in the narrative proper.
See for yourself if the narrative flow of Captain America: Civil War was superior to that of Batman v Superman: Dawn of Justice, as both films are currently in theaters now.
