You say this with an assuredness that you can't have unless you work for DC Comics. I've looked at the way that symbol is depicted more than once in the last few days, and it's definitely a 3D shield with details that indicate a solid, raised material.
Reeve's symbol was not at all this way, so I'm afraid I don't see the connection you're making there.
Not only what he did to Kal-L, but also Superboy of Earth-Prime, who I loved as a big fan of the Bronze Age and especially Elliot S! Maggin. I'm not saying I think this is a good idea, I just think there are a lot of clues pointing to it being a real possibility.
Excellent point. Manhattan wasn't evil at the end of Watchmen and hadn't "abandoned" his humanity, so it would make sense that none of this is his doing. Unless he lost the regained faith he had in humanity after exploring the Multiverse (and perhaps Multi-Multiverse).