great modern western, but the end would have been ever better if..

hi,

i liked the movie and the end too, but there was another possible end which would please me very more :

imagine that :

i thought the couple (david and his women) would prepare their plan before they went to the town. i thought the wife would plan to be near of the bad guy and to seduce him to get confidence, the thing about the health problem too (a liar)...
So, at the very end on the rock, his wife would save him instead of Maria did.

If the whole plan would have been forecast, it would be wonderful.