Aristotle did not really clearly favor any one form over another. If you consider the 3 available types, monarchy, oligarchy and polity, he probably favored the last type. That is the polity which was made up of the largest group of individuals and had the least chance to do real harm to the state. While the oligarchy made up of the aristocracy and the monarchy made up of one ruler, had the greater chance for harm because action could be initiated by fewer individuals. Aristotle almost always favored a middle (mean) position to one of the extremes.