I get your point, but there's a bit more nuance than that I think.
Keeping actors really good in their roles isn't doubling down and what's not working, IMO. It's taking the best from what, to your point, largely failed.
Who wants the Authority? Do you think that's going to "work"? Before a Justice League movie?? (no Justice League movie has even been announced, btw)
Their first Batman movie they are going to have is The Brave and the Bold. It's a good story in the comics, but how about we actually have the origin story of Robin and their relationship?
When has a Swamp Thing movie ever worked?
Creature Commandos. 'Nuff said.
Oh, and let's not forget their Game of Thrones series set in Themyscira.
My plan sounds better than Gunn's. And now that consumers are actually discriminating with their dollars and not paying for crap, time will tell if choosing Gunn and his complete redo was the right move.