Hmm, well it seems that the cast members real life personas somewhat reflect their characters', even in small ways.
Superman is your quintessential all-American, without actually being from America. He's humble, hard working, and a man of the people. His arrival was wholly unexpected, but in a great way.
Batman has been through some sh**, but he masks it all behind the character he's created to appease his audience so to speak. He's more intelligent and capable than he lets on and he's at a point in his career where after so many uphill battles, you'd think he'd be worn down, but all it takes is a new challenge to show he's got plenty left in the tank.
Wonder Woman is tough as nails and from a place most of us know very little about. She's underestimated because of her beauty and womanhood, but there's a strength in those things that will likely surprise and inspire.
Lex is highly intelligent and can be charming as all hell, but there's a ruthless cunning that waits for the right time to strike. You only think you know what to expect from him, but there's a definite darkness just waiting to see the light.
I know these aren't perfect representations of the characters, but the similarities they have to the actors are definitely obvious. And the actors all have the fact that they had/have to prove themselves to fully garner fan support.
So all that being said, I think whoever is cast as The Joker will be off putting at first, but people will come around when they realize how much that actor actually represents the character they're playing. It'll have to be someone manic, but engaging. Someone who can make us smile shamefully at even the worst atrocities. Someone whose insanity is their most endearing trait. He'll have to be controversial enough to get the fanboys going (for better and for worse), but ultimately reasonable enough that we'll all come around.
Here's my list of potential, actual weird people You will probably hate many of these choices and that's sorta the point:
Nic Cage
Matthew Mcconaughey
James Franco
Tilda Swinton (that's probably the most out there suggestion)
Tom Cruise
Shia LaBeouf
Joaquin Phoenix (isn't at all off-putting, but he had his time hoax or not)
That's all I got for now.
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