Actual SUPERMAN, however, isn't exactly portrayed as a guy fighting his inner demons for control. Nor is he Spock wrestling with emotions. The guy is just a boy scout, super-do-good'er, so releasing his inhibitions really shouldn't make much difference, since he's a mid-western, mild-mannered, aw shucks kinda guy anyway...
Superman does have inhibitions. He won't kill people who've really made him angry, for example. He also won't conquer the world for the greater good. Superman without inhibitions is basically Justice Lords Superman. He won't kill unnecessarily, but he won't have many qualms with brain surgery. Whether that is a good thing or a bad thing is a matter of opinion.