I recently came across this 2013 article from the journal Jesuit Higher Education, which provides a thorough overview of various terms within Jesuit/Ignatian education, focusing specifically on the meaning of magis. The article, authored by by Barton T. Geger, S.J., contains this entry (for example) on the relationship between "magis" and "social justice":
First, to be authentically Jesuit, social justice must be considered means to a higher end, namely the sevice of faith. The ultimate goal cannot be creating a just society for its own sake (secular humanists seek as much), but rather bringing people to faith in a personal God who loves them. The Fathers of [General Congregation] 32 had this in mind when they made a careful distinction that "the mission of the Society of Jesus is the service of faith, of which the promotion of justice is an absolute requirement." For Christians, an eternity with God and the blessed in heaven is the greatest, most universal good that any human being can possess. Thus the magis by definition always points Jesuits and colleagues toward that ultimate goal."