sorry guys, but you do have one thing wrong, Cloud wasnt looking for Aerith. He was looking for the Sephiroth. the text between the two in KHFM shows that Aerith isnt acctually who he is looking for, but rather, Seph. If I recall correctly, something about Seph. haunting Cloud's dreams. Those who have seen Advent Children see that is more or less the same. In fact, If i once again recall correctly, the final words that Sephiroth say in both AC and FM are in fact the same, "I wont be just a memory"
so as far as Cloud having his own story, and judging how AC seems to tie in with Clouds story, odds are hes once again looking for Sephiroth, to probably finish the job so that he can rest easy knowing that Sephiroth is finnaly defeated.