...I probably am being too harsh. And I didn't intend to imply that Berlin and Ueno were comparable in what they achieve, but rather in what they (seem to) strive for.
Well, they're both urban zoos that strive for something like an encyclopaedic collection. I think that's a mistake for both of them, though moreso for Ueno, which is half the size. I think Berlin would benefit a lot from taking advantage of the Tierpark's existence to rationalise its large mammal collection, but as I said above there's only a handful of other major zoos that I think cater to them consistently better (on reflection I should have added Beauval to the list though).