You know, in One Piece. Self-inserts alway talked about how bad the government is or the problems cause by them but none of them ever do anything about it. In fact, most of them ends up being pirates, adding more to the problems that already existed.
For once, I like to see one where the MC build an empire beat the World Government. It's not even that hard(in writing that is) to do so. If the self-insert just uses his brain, he'll have notice so many opportunity to amass an army to fight against the World Government. In fact, they can even upgrade the weapons of the world to turn the fight against the World Government in their favor. If the author make the MC a engineer, he can have the MC build basic planes before gathering a group of people to design better planes to help fight. Once they have control of the air, they'll basically win half the battle. Next, they just have to train or recruit powerhouse to go against the powerhouse of the World Government while the Air Force deals with the Navy.
I'm rambling again... basically, I just want to see some kingdom building in One Piece where the MC finally get rid of that useless, corrupted, annoying World Government.