I was thinking about this recently. A lot of Suicide Squad members are from Batman's rouges, I'm not saying I only want Batman villains inside the Suicide Squad but say if DC split up their IPs similar to Marvel, and a company was only able to use Batman-related villains/characters. What would the line-up of the Suicide Squad look like?
I want this to mainly be a discussion but I think if it was mainly Batman-focused, you can see a lot of lesser known Batman villains, like the C-listers. Or non-insane villains. You can include Harley Quinn but I personally feel like she just has kinda over-taken the team in a lot of ways, that so many people feel like she's a core member. I don't hate her, but I wouldn't mind seeing a version where she isn't in it.
Deadshot - He's in a lot of Suicide Squad adaptations and comics, sometimes even as the team leader. He's even considered mainly a Batman villain so it makes sense.
Polka Dot Man - I loved him in Suicide Squad 2021 so I'd definitley include him.
Killer Croc - Besides just being seen as a popular member by many, I just think he has a lot of potential. In certain comics, Croc is portrayed to be this sypathetic person who just wants to live a normal life, but can't cause of his skin condition. I think having an arc where he learns that the Suicide Squad can be his found family, for people who can finally accept him can be great.
Killer Moth - I love the guy unironically. I think Moth can act as a sort-of straight man to everyone else. I always found the charm of Killer Moth is that he was some guy who thought he can do what Batman does. Taking a regular guy and throwing him in with everyone else could be really cool to see.
It's also a shame because all three of the previous members I've mentioned have been members in movies and adaptations. Moth has only had three appearences as a member of the Suicide Squad, but as cannon fodder! Once as fodder in the Injustice comics (he basically dies right away), and twice in the Arkhamverse (both the Suicide Squad movie and game) where he was mentioned as a replacement for Task force X. Just give him his moment to shine!
Calculator - Recently, Calculator has been portayed less like the goofy calculator-dressed badguy and more like a computer guy, being a computer genuis. I think this role could work on the Squad.
Eraser - His whole gimmick from his first comic was how he eliminated any sense of a crime, almost like he "erased" it away. I think retooling it to be a crime scene cleaner for the mob could be really interesting. Not to mention how Waller wants to keep Task Force X in the dark, so having someone specifically on the team to get rid of evidence could be really cool.
Any other Batman villains you'd want to see in the Suicide Squad? Or maybe I could do a version of the squad that can feature rouges galleries from other villains.