I don't consider myself a purist. I had no problem with Superman killing Zod in MOS. Also wouldn't have had much of an issue with Batman killing in BvS had they given it more weight, and emotional drama. They didn't, though, and Snyder's main excuse seems to be pointing at other films where Batman has killed, so his Batman killing shouldn't be a big deal. Yea, way to go champ. My main issue, much like it was with Nolan's Dark Knight and Dark Knight Rises is they have taken the "super" out of super hero. All Snyder has done is make Watchmen again, but this time it stars Superman and Batman. I have no issue with a more serious take, but these things have been serious as a heart attack, and just not very enjoyable. And people will say, "Well just wait until Justice League! Wait until MOS 2!" Blah, blah, blah. That's all fine, and dandy, but when Superman is going to be a supporting player in one film, and the other film isn't even guaranteed, you'll excuse me for being a little impatient when it comes to wanting to see a Superman who doesn't have a giant pole up his you know what.
Also, when a director says his idea of having fun with a character like Jimmy Olsen is putting a bullet in his head, and also openly admits that he didn't give his heroes a lot of dialogue in costume because he doesn't think it would be taken seriously, I think it's pretty obvious he's the wrong fit for this material.