Perhaps Rome should start with a law that forces it to use the pre-Marian system, in which cohort loyalty mechanics are disabled but you gain manpower at a very slow rate. Passing the Marian reforms could grant you more manpower, but at the cost of enabling cohort loyalty mechanics. Upkeep and morale could also vary depending on what laws you use.Yes, cohorts should become loyal "only" through when they actually do something with their generals, meaning fighting and winning wars, and when their generals pays them more directly, bypassing the state.