Batman see, Batman do, as they say. Although Ace and Krypto were a mere three months apart in terms of their first appearance, it's hard not to see Ace as some sort of rip-off, but he's much more than that. As much as Ace's inspiration clearly came from Krypto's introduction, Batman's loyal dog has gone on to become one of the most recognizable comic book animals ever, having also appeared in the Krypto cartoon as a recurring character. In the DC Cinematic Universe, it would be absolutely incredible to see Affleck's Batman have Ace. One of the things that we know for sure about Batfleck is that he'll be older, in a more cynical place, so it makes a lot of sense for him to have taken up a pet in his isolation. He may not ever wear the famous costume that Ace wore, but it would be criminal to not show Ace hanging out in the Batcave at some point during Affleck's run as Batman.
