Brutus in "Brutus No. 1" opposed a strong central government because he believed it would weaken the authority of individual states, potentially undermining state-level pluralism.
Madison in "Federalist No. 10" supported a strong federal government within a large republic to preserve pluralism. He argued that the diversity of interests and factions in a large country would prevent any one group from dominating, thus safeguarding pluralism at the national level.