-sorry, I meant to type "different director". That's my bad.
-sounds like you want how they'll probably handle Supergirl. In the Supergirl: Woman of Tomorrow comic mini-series (which her film will be a direct adaptation of), she's definitely not fully cynical, and does adhere to the "no killing" rule, but she does have a tad less idealistic view of the world compared to Superman, but she can show compassion and kindness and is shown helping people in need. So she could provide the foil you were looking for in a superhero adjacent to Superman
-nah, he only went nuts on The Suicide Squad because, well, that's their concept (the first movie barely killed off anyone). I think there's plenty to do with Guy so he's probably safe, and I highly doubt he'd off Mr. Terrific and Hawkgirl. I assume Metamorpho has less screentime so he'd probably be safe for now as well
-yeah, but like I said, they could find a way to revive Hal with a new actor, or go the Spectre route which would be cool
-yeah, originally James Gunn said they'd keep the Blue Beetle film as canon (as it was mostly isolated from the DCEU), but he changed his mind so it's non-canon now. But they are planning a Blue Beetle animated series and Jaime's actor will reprise his role as the voice, hopefully that means they'll more closely adapt the 2000's Jaime Reyes run which is amazing (while the movie was just okay and did its own thing which was kind of just average to me) and since that run actually has both Guy Gardener and Peacemaker play a decent-sized role they could have Nathan Fillion and John Cena reprise their roles (as Gunn says he wants to keep the same actor for both live-action and the voice for animated when it comes to any character appearing in both formats).
Booster Gold is getting his own show, and Ted Kord (the Blue Beetle before Jaime) is Booster's best friend, so Ted will likely appear as well