I am not sure I follow you, Alex. What does consilium have to do with God "planning?"
I don't see what is so good about "economy", it is an awkward term, at least given the modern connotations
The "economy of our salvation," in short, is how God revealed himself to man, namey as three different Hypostatic realities, and how each reality revealed what man should do to be saved. That's all. That's not "planning"; that's doing.
Needless to say, the economy of man's salvation is about as much a corruption of Judaism as Mormonism is of Christianity.
consilium: A conclusion made with consideration, a determination, resolution, measure, plan, purpose, intention
But the Catechism doesn't say a Muslim has to convert
Because formal conversion may or may not happen. We believe in sovereignty of God, who, in His mercy can act in non-ritualistic ways.