You could move Artist-boosting potential to a Hollywood wonder, and have faith from Cristo Redentor.
I think it'd be better to let Cristo Redentor as it is now . The faith bonus doesn't make any sense,as there aren't any kind of religious Pilgrimage to that statue,to justify the faith bonus . Plus,the current bonus in Civ5 fits even better than the bonus of Civ4 .
That's also the biggest problem for late game wonders, that runaway science civs can build them all quite easily. Apart from prohibiting runaway scientists, creating more wonders in the late game then actually combats that effect, not adds to the problem.
One solution to this problem is to make everyone receive a free spy once the first player hit the Industrial/Modern/Atomic/Information age .