Based on those pics above, Affleck might pull off the look. My biggest concern was can he pull off Batman the person? I think he'd make a great Bruce Wayne, but it's very hard for me to picture him all grim-and-gritty like Batman (modern Batman anyway; I could see him playing the cheesy, campy Batman of the 60s).
And Cap, it's funny you say that about Damon. I did read an article about a month ago saying that there were rumors out there that he's being looked at for either Martian Manhunter or The Flash (I think, might have been one of the Green Lanterns).
Somewhere, can't remember if it was here or elsewhere, someone was talking about the need to fast track the introduction of the various members of the Justice League for a new JL movie. IMO, they really oughta look toward Arrow for that. This season they've already said they're introducing The Flash (who's then supposed to go on to have his own movie or TV show, can't remember), Black Canary, Red Arrow, among others. Marvel's tying their movie universe to a TV show on ABC, why not do the same for Arrow and DC's movie universe.