It's only my own opinion, but I believe there is too much centralization of national, international and diplomatic institutions inside the City of Paris. I am _for_ more decentralization of businesses and powers across the Region of Paris and across other cities of France. House pricing clearly shows that the City of Paris is a gravity center in terms of everything, which leads to many of the current traffic and pollution issues imo. Maybe a decentralization of France's institutions, powers, businesses etc could help it?

Edit : Idea : at each new presidential term, move all institutions and the french "white house" to Lyon or Marseilles, second biggest city of France. At the next presidential term, move everything again to Paris.