I'm not talking about the characters, but the actors. Marvel has hit the nail bang on the head with their casting, and virtually all of their actors/actresses have come across as fun, likeable people who seem to have a great time doing their job together. RDJ is the only one with any scandal of note, and even that was a long, long time ago - he's turned his life round completely.
DC for the most part have also cast wisely; Cavill is a great Superman and also a great ambassador for Superman, just as Reeve was. Miller is a lot of fun, as is Momoa, and Gadot/Fisher seem like great people also. Affleck is slightly different; he always seems a little disjointed from the rest of the group in interviews and so on, and I'm not sure if this is a personal thing or just his manner. I have zero interest in his personal life but it would be foolish to deny that reports of affairs, alcoholism, ties to Weinstein and so on have not had some kind of effect; that much is evident from some forums and media sites I've seen.