DCEU: 9 New Revelations About DC's Future Movies
6. ...And Harley Quinn's Not In It
Unfortunately for Gunn, his soft reboot probably can't use the same characters as David Ayer did, because nobody wants that much proximity to something they're seeking to reboot. If he's truly doing it "softly" as suggested, he could be bringing back some of the cast - for instance, not using Will Smith and Viola Davis at least would be a mistake (and to be honest, Jai Courtney deserves it too), but it's unlikely he's going to bring in a new Killer Croc or Boomerang straight away.
One thing you would have though he WOULD do, though, is bring back Margot Robbie's Harley Quinn, since she's definitely still an active character on Warner Bros' DC slate. But Forbes now say that Robbie definitely isn't going to be in Suicide Squad (or The Suicide Squad as it's currently being called).
Perhaps Gunn really is focused on distance from Suicide Squad if he's willing to put aside one of the things that genuinely worked about it?