It's almost like #1 needed just a bit more rock on the side against the returns. That would have made it so both sides looked fairly equal with a smaller center. Still have lots of open space, which is good, but it would have been more balanced. In #1 the side against the return used to be less substantial that it's counterpart on the other end of the tank and in #2 it's gotten quite a bit more substantial than it.
Of course both do look good but if I had to absolutely choose one, I'd go with #2.