I still want a Justice League movie starring Superman, Batman, Wonder Woman, Cyborg and Zatanna. Not too many characters, a good male to female ratio, different power sources and abilities and easy to introduce.
: I'm permanently pissed off, I fight crazy guys and prefer to lurk in the shadows.
: I'm the sole survivor of a distant planet and have incredible abilities but I grew up here on earth and my mom's pie is the best in the world!
: I'm an ambassador of peace from an advanced society hidden from the rest of the world, but I won't hesitate to punch your lights out if you force me to.
: I'm a cyborg!
: I can do magic!
Seriously, the last two aren't well known outside of the comics but they are very basic and well known ideas, the audience will understand them without any big introducton, they are pretty much self explainatory.
Characters I wouldn't use are:
(to similar to Superman's origin, one lone survivor from a different planet is enough)
(his movie was a flop, he could work on Justice League but there's no reason to risk stinking up the movie with GL's smell of failure when you have a rhousand other characters to choose from)
(he's fast, everything he can do can be done by Superman ... yes, I kow, he's faster than Superman, whatever, in a 2 hour movie it's easy enough to have Superman be fast enough)
(it's hard to make him useful on land, so unless you want to introduce an underwater lair or a secret underwater entrance for him to infiltrate a base or someting, leave him out)