Earlier in the thread, there was some discussion about whether the World Government would listen to Sengoku's recommendation and appoint Aokiji as the next top model fleet admiral, or whether they would choose Akainu instead.
I believe that they'll go with Aokiji, if only for a while. As the story progresses, though, I can see the already-corrupt government and Marines growing steadily more corrupt, power-hungry, and desperate. Aokiji will somehow lose his position (either by dying or defecting from the Marines) and Akainu will take things over after that.
I'd like to see some of the Marines uncover the corruption of the World Government and form a group of renegades. In this group I can see Aokiji, Smoker, Tashigi, Hina, Jango, Fullbody, Coby, and Helmeppo, all of whom are, on several occasions, shown to be less than dedicated to Akainu's brand of justice.