Any team that includes the Joker is definitely living up to the name "Suicide Squad"....
He won't necessarily be on the team. I wouldn't be surprised if he were the villain that the Squad was sent up against. After all, the way to make villains sympathetic is to pit them against an even worse villain, and the Joker is the worst there is.
To be honest, while perhaps Suicide Squad won't be "Will Smith and some other people" I can see them putting a bit more of the focus on Deadshot than on the rest of the team, similar to how they handled it in Batman: Assault on Arkham.
I haven't read the comics, but from what I've read about them, I had the impression that Deadshot has usually been the central character, or at least the heart of the ensemble.
Anyway, I'm pleased to hear that their candidates for Waller are rumored to include Oprah Winfrey and Viola Davis (whom I've thought of as a good candidate for Waller). They aren't anywhere near the character's original girth, but at least they aren't thinking in terms of the young, supermodel-skinny Waller of The New 52 and
Arrow.