vidsgame: The Batman Games sort of kind of come close to this but they have less RPG elements.
As others have said, the open world has to be done right but otherwise this sounds like a really neat idea.
A while back I played a third-person Iron Man game on a console at a store and it was rather a good time.
Something open world would be great granted that it is done right.
I have been tempted to pick up Freedom Force several times only to re-read the description and go "darn it".
Anothername: Elmofongo might correct me as I might have read too much of my own wish list into it but if I read the OP correctly the Arkham games have the same disadvantage that recent Spider-Man game has: Batman & Spider-Man. You do not create your own hero in there.
Open world with a premade are quite a few. But one where you have:
- open world
- full customization of a characters race/gender/costumes
- full customization of super power abilities/skills
- a personal story-line
have; aside from Saints Row 4, never been made. And as fun as SR4 is; it never really feels as if it is an intentional SH game.
That's true. There's no hero creation but there is definitely room in those games for abilites, skills, powers, costumes, personal story and different characters depending on the game.
For characters, they could just call the game Gotham and let you pick different characters from the comics that take place in that city. You could then sort of customize the face.
However, it may be easier to go the Witcher route in the Batman games in case someone were to desire an RPG out of Batman. It could certainly be done as Bruce Wayne is the sort of person who has his own storyline that varies throughout depending on what you're reading.
Of course, there is more than enough room to come up with something original as well like Agents of Mayhem has done.