He also has the rare distinction of being one of like 3 characters to have appeared in all 4 major 'Crisis' events and lived, beyond the core JLA.
For me, personally, I would love to see some wildcard entries in the game, or at least unique characters.
The Atom - While he may seem impossible to implement on a gameplay level, there are ideas I have to make him work. He would truly be a 'wtf' character choice.
Red Tornado - A wind elemental android. Think Fujin, but y'know, playable.
Clayface - Hulking shapeshifter/stretchy character.
Blue Beetle - As much as I love the Ted Kord version, his legacy, Jaime Reyes, would offer up a much more unique playstyle. Something similar to Cyborg with far greater mobility.
Dr. Fate - I imagine him as more of a magical/zoner playstyle.
Mera - Essentially a water elemental.
Director Bones - Truly the most oddball of my picks. His playstyle would be nothing special, but aesthetically, he's badass.
Tattooed Man - A villain for hire who can manipulate his tattoos to come to life.
Ragman - A mystic who collects a patch of cloth of those he finds guilty of sin, and gains there spectral strength. Now that I think about it, VERY reminiscent of Ermac.
Orion - New Genesis' god of war. Often depicted with some kind of weaponized jetpack.
Stargirl - Her star staff would make for a good playstyle, if nothing else.
Black Lightning - The OG Static.
Damage - A brawler that can expel bursts of energy/explosions.
The Question - Also a brawler but with his main fighting style leaning more towards martial arts. A guilty pleasure of mine.
Circe - A Wonder Woman villain, sorcery character, as well as having a penchant for turning people into animals.
Shadow Thief - His powers are, you guessed it, shadow related. Could be very unique if executed properly.