Sorry, I absolutely understand where you're coming from and 99.9% of the time I am right there with you.
Not this time. This isn't a multiverse comic, this is this character's FILM EXISTENCE. Cassandra Cain is not a high school Harley Quinn flunky who has to shit out diamonds she swallowed. You're saying you'd be totally fine with a movie where Wally West was a football jock who gained his powers after getting wasted at a high school party and tripping into a ditch with radioactive waste? Or if Batman were a gambling adict who took up the mantel to beat up bookies?
There absolutely no basis for it. There is no reason for this character to be Cass.
Saying this is a fine incarnation is the same as saying that you are totally cool with the timeline where Wolverine Origins Deadpool is the Deadpool everyone associated as his primary representation in modern media.
Mate, they literally have two Jokers and might get a third... Their whole idea is to just make standalone films.
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I just decided to change this sig. Blaaaaaaargh Advokaiser