I feel that If DC just copies the line up for Marvel's characters for Avengers by just replacing each Marvel character with its closet possible DC equivalent for JL, it will look like this -
Nick Fury - Amanda Waller.
General Thaddeus Ross - General Sam Lane.
Hawkeye - Green Arrow.
Black Widow - Black Canary.
Iron Man - Steel.
Captain America - Guardian.
Thor - Captain Marvel.
Hulk - Captain Marvel (same as above.)
So, basically JL movie equivalent of Avengers is -Green Arrow, Black Canary, Steel (or Cyborg), Guardian and Captain marvel.
Now it is not the well known iconic team but if we consider it for a moment, it becomes apparent that this team looks more grounded and it will cost much less if this team is selected, but as it is not popular it will not do as well as Avengers will (I know many will say that each hero in Avengers team has got his own movie first) even if WB were to make a movie for each of thse characters and then make a JL movie consisting of this team up it will not do well, this is the advantage Marvel has.
WB will have to make a JL movie with their iconic characters and each of its members will have to appear in big budget movie, characters like Green lantern, Wonder Woman , Flash require big budgets.