Batman Forever does something that Batman and Batman Returns were unable to do: it makes Batman a proper protagonist, with goals and desires of his own. Not merely reacting to events, Bruce/Batman is after something in Forever. His various allies and antagonists, seductions and betrayals are all thematically consistent and relevant to his struggle. This does not mean that the finished movie is without flaws.
WHAT DOES THE PROTAGONIST WANT? Bruce Wayne wants to lead a “normal life.” He wants to be able to fall in love, put his demons to rest and have a fully integrated personality. Life has, as life will, other plans, first in the form of Two-Face. Just as Bruce is motivated by an unending revenge for his parents’ death, Two-Face is motivated by an irrational desire for revenge upon Batman. Two-Face’s sense of justice (arbitrary and cruel) and divided-down-the-middle personality are twisted mirrors of Bruce. Bruce would love nothing better than to put away Two-Face, settle down with that nice Dr. Meridian (astonishingly, yet another blonde with a bat obsession — how lucky can one guy get?) and hang up his cape for good.