Being built in the same archetype, Icon obviously has many face value similarities to Superman. Due to this, many may feel that he is too redundant to be in the same universe. Many who are ignorant of him simply write him off as a "Black Superman". Upon pondering, this creates a perfect challenge for a Geoff Johns-esque revamp!
Let the first arc be not so much an origin so much as a "response" to the first adventure of Icon and Rocket. Similar to how Johns' Aquaman run has addressed many of the ignorant assumptions on that character, an Icon mini or backup could help to due the same for Icon. Have the news refer to him as "the black Superman" of Dakota City, with reporters asking him if he is a member of Superman's race.
Though many Milestone books did not feature race as a prominent issue (as opposed to what many ignorant detractors believed), Icon was definitely a book that dealt with race issues, class warfare, conservatism, rising up out of the ghetto, minorities within minorities, and clashing ideologies. THE CONTROVERSY ALONE COULD SELL A BOOK, DC!!!! Namely the fact that not only would a comic book, a medium whose creators are usually more liberal, is coming from a more conservative standpoint, but the fact that it's a black character whose voice is saying these things. Icon himself could question why he has to be the "Black man's Superman" and what that truly means. If done well, it could easily elevate the book beyond just "big dumb punching" and into something great.
Another area that Icon desperately needs in terms of definition is a real rogues gallery. Though he had a few foes, Icon mainly fought other people's villains, such as Holocaust. Give him enemies! Have villains who just happen to want to fight Icon, have villains who may happen to be racist, have villains who are also black! The other black villains could either be gang member bang babies, or people who actually think that Icon isn't black enough (going back into the race issues).
Seriously, DC is sitting on a goldmine when to it comes to Icon and other characters.