I think one interesting comparison no one is making is Aeroplan. They are of a similar customer size and very similar in terms of large partnership offerings. They recently updated there program to go points per dollar for status and they have multipliers in place for status. The higher your status the easier it is to maintain status.
I know we love comparing to the Big 3 but I think our northern (southern?) brethren have the most similar program and a much better earning policy for their loyalists.