I can't believe somebody wrote "Dump Gal"...
If they reboot and dump Gal, then if in their reboot the new WW is a complete disaster, then what are they going to do? WB would be the laughing stock of the town for dumping a beloved actress in the role after such a successful movie only to replace her with someone else who could turn out to be a flop.
And what if the rest of the new reboot is a flop, or alternatively, they manage to be successful with everyone else except for Wonder Woman?
When EON rebooted James Bond for Casino Royale, they still kept on Judi Dench, who was M in the previous continuity, because they liked the actress. They didn't care that she had just played in the Pierce Brosnan films where there was a Bond who was in the middle or end of his career and now was M at the beginning of his career.
And the general audience got over it and accepted her, even though it might not have made sense. People just took it as a different M but played by the same actress. Or they forgot. Or they just overlooked it and didn't care.
They can do the same with Gal. Even if they reboot everyone else around her, she could be like Judi Dench and still be carried over from the old continuity. After all, she is the only one in the DCEU who is universally loved and who has been mega successful. She is really the star of the DCEU when you think about it.
And thinking of other examples, Christopher Lee played Dracula several times in different movies, even though in each one he died at the end.
And in the Sergio Leone Dollar Trilogy, Clint Eastwood's character, the Man with No Name, remained constant as a character. But what was interesting is that they often reused the same cast from previous movies but as different characters.
So Gian Maria Volontè played Ramon in A Fistful of Dollars (but was credited as John Wells for that movie), while in For A Few Dollars More, he used his real name but played El Indio. Similarly, Lee Van Cleef played Colonel Douglas Mortimer, an ally of the Man With No Name in For A Few Dollars More, but in The Good, The Bad and the Ugly, he was now a villain named Angel Eyes.
And there are other examples. It's been done before in many movies. They can keep Gal even if they change the cast, and it won't really confuse the audiences. They'll learn to accept it.