Last week actor Frank Grillo took a meeting with Marvel and tweeted about it. Somehow he still got the job he was going for - the villain Crossbones in Captain America: The Winter Soldier.
Crossbones is a weird character, mainly because he's not that interesting. He's a thug, more or less, a glorified henchman. Usually for the Red Skull. Crossbones' biggest moment came when he 'assassinated' Captain America at the end of the Civil War crossover (I put 'assassinated' in quotes for a whole host of reasons). At that time he was sleeping with the Red Skull's daughter, Synthia Schmidt, aka Sin - this was all during the Winter Soldier storyline that re-introduced the previously-thought dead Bucky Barnes into the world as a Soviet-brainwashed super assassin (it's so confusing when explained like this).
ANYWAY. Crossbones, this thug, was sleeping with Sin during the storyline that brought Bucky back as the Winter Soldier. Recently there was a casting rumor that had Alison Brie and Emilia Clarke and a bunch of others up for a role in Captain America: The Winter Soldier, and everybody assumed it was Sharon Carter - niece to Cap's WWII girlfriend, SHIELD agent and current love of his life. But what if the character is Sin? What if instead of the Red Skull (since Hugo Weaving doesn't want to come back) we get the daughter of the Red Skull?
I'm just spitballing here. I feel like some of Ed Brubaker's early stories on Captain America are perfect for adaptation, and a slightly massaged version of the Winter Soldier storyline could kill on screen. I don't think much has to be invented, honestly - transposition will work.