To answer the question, I usually put my worst outfielder in Right field based on the notion that there are more right handed hitters pulling the ball to left field. However, experience has taught me that it doesn't really matter - if it's a late inning situation where you desperately need a win, the opposing team will invariably hit a deep flyball to the worst outfielder (wherever you try and hide him) who will then boot it for a 2 base error leading to a heartbreaking loss.