If removing bonus miles stems from the obvious financial issues, then I can see a few ways to produce the same result:
1) remove the bonus miles (affects only elites)
2) increase the mileage requirements for redemption (affects everyone)
3) decrease redemption availability (affects everyone)
Seems as though #2 and #3 would be sufficient. AA has recently decided to implement #2, and it sure seems as though #3 is in effect (IME it's harder than before to score a 90k business AAward).