I haven't read the whole thread, I'm just gonna drop my opinion. And agree with Max on I, Robot. That was a great movie.
I think personally the whole director thing boils down to who will do the best job on a given movie. I think I said this in the thread sonic made about yes men. Using a big name director isn't always gonna give you the best results, and why some complain about Will not using big name directors, I see no real evidence that anyone else could have done a better job directing. Obviously there is o evidence on the counter either. But a great movie was created with POH, and the only thing I didn't like about that was the chemistry between Will and Thandie, not the directing.
Sure he's the biggest Hollywood star at this moment, but that doesn't mean that the best directors in the world will always do the best job on a WS movie. I think it's great that he's using lesser known directors at this point, because it gives them a chance to get established, and it hasn't damaged Wills cred at all, in fact after using Muccino, its enhanced it. The Spielbergs and Scorcese are not always gonna be here, so its good to get the lesser directors coming through. To me thats like saying, Will is too big to be working with the smaller directors, if you have that mentality, you have an ego, and you think you're too good to work under a director whose not well know. Thats not the mentality to have. You pick who you feel is best for the movie, Scorcese and Spielberg aren't always gonna be the best choice.