Thanks, Poppadom_Pete, for guidance on the onions.
I agree that the real differences occur in the final cooking, and, as George says, balancing the garlic and onions (and spices) of the base sauce to make the final dish. I have two base sauces in my freezer, one bland and one spicy, and that's what I do. Or should I say, that's what I try to do. ;D