After watching the newly released trailer i've been thinking what directions Ben Affleck could take the standalone film in, here are some ideas:
3. Death In The Family/ Under The Red Hood:
In the trailer you see Bruce Wayne walk by a suit. This suit look to be Jason Todd's suit with Joker's writing on it (as indicated by the HAHAHA). The importance of this is in the comic book arc of 'A Death In The Family' Joker killed Jason Todd then Bruce replaced him with Tim Drake. After a while, Jason is resurrected using the Lazarus pit and trained by Talia Al-Ghul to become a deadly assassin. He then returns to Gotham and begins controlling it to get Bruce's attention. Then after getting it, Jason kidnaps the Joker and forces Batman to choose who to kill, Jason or Joker. In Batman-like fashion Bruce saves both of them and puts Joker and Jason in Arkham. Since seeing the suit I feel like this is one of the most likely scenarios, but Ben Affleck could get creative with it and make it his own.
2. The Killing Joke:
If DC decides to take the prequel route they could use this story, plus with DC trying to become the dark, gritty beast of the comic world The Killing Joke could be a perfect way to cement that title. It starts with the origins of The Joker who has a failing career as a stand up comedian. With his career failing the way it was he agrees to aid a group of criminals, this leads to a job being slammed to a halt by none other than the dark knight himself. While the fighting took place he falls into a vat of chemicals and becomes horribly disfigured. With his life falling to pieces he becomes insane and uses the persona of The Joker. The main plot would be The Joker trying to drive James Gordon insane, this would give Ben more creative direction since it wouldn't be constantly focused on him as Batman. Long story short, Joker does horrible things to Barbara while forcing Gordon to watch while humiliating Gordon in the process. Batman finally manages to put an end to The Joker's soiree and Gordon retains his sanity and moral code. This story along with the grit and gore would be perfect for DC, as well as show off how Batman and Joker are mirror images of themselves with different choices in the end.
1. Original Story of an Owlman face off:
There have been rumors floating around that the standalone film will be featured around Owlman being the main bad guy. In this case there are a ton of directions Affleck could go in. He could open up the multiverse and so many other options. This in my opinion will be the most likely option to see, but also very risky. It's risky because Affleck would have complete creative control, which could be a bad thing or a very, very good thing if you've seen Argo. Now, with that being said, it could lead to the complete and total rebirth of a very interesting Batman villain, Owlman.