The essential idea that we're all imagining for the Suicide Squad video game is that there will be lots of characters, and that each of them will feel unique when played. Maybe Harley Quinn uses her mallet and agility, but Deadshot needs to use positioning and range.
That being said, many of these characters are classic DC names. Having imagined them dozens of ways over time, the Suicide Squad game could really draw in the super-fans with different movie and comic character skins.
If it's too much to ask, at least offer more characters and skins as premium content. It's not like it would be a major shift from current studio income strategies.