Kyle ~
The thought of a new tee for tournament play for #6 behind the new 5th green could bring a little excitement and surely make the course play more difficult at a par 70 (in relation to par anyway) However it would make the front nine a par 34 assuming #2 plays as a par 4 as well....give a little take a little I guess.
If a new tee is not an option, changing the 6th to a par 4 would not affect the players in an Open, USGA Amateur event, or the AT&T because they will all be playing the same hole in relatively the same manner. I recently played a tournament where two par 5's were moved up a little and played as par 4's....so par changed, big deal...Everyone plays the same hole, same yardage, same par. You don't necessarily think about the tee shot or playing the hole differently because you're still trying to make 3 or 4 whether it's a par 5 or par 4.
However, I do think it should remain a par 5 for the public regardless of the tee location because of the blind second shot and the length...
~The New Guy (Nate)