When comparing alternative 1 and 3, using alternative 2 as base, I usually think like this:

Alternative 1 Miles/dollar = 55000/1100 = 50.
Alternative 2 Miles/dollar = 66000/1600 = 41.25.

and this is still not taking in the equation that you might get some miles on LAN (AA?) for future fun. By this we can see that is is not even close, alternative 1 is better than alternative 3. The only thing that could change my mind here if you are either close to a status level that the 11k miles would put you over, or ifyou are saving miles for a honeymoon.

So when we have disqualified option 3, you will have to decide if 1/50 = $0.02 is a good value/redemption rate for your miles, and that depends of course on your economy, future travelplans and similar stuff. It is a close call, your decision.