Since CO2's the prevalent gas in the Venusian atmosphere, would it make sense to make CO2 available there as an RCS fuel? Presumably the belt affiliated parts of the solar system uses nitrogen harvested from outer planet moon atmospheres, but Venus has CO2 right there.
As part of the this, if it's not already accounted for, CO2 use should reduce thruster output by ~16.25% to account for reduced Isp.