Very well put, dublinlion. I was lucky enough to have visited London in the 1960s and 1970s when a full day would still leave exhibits unvisited. I'm not naive to think that it was perfect at that time - it certainly wasn't- but a lot of posters here don't seem to see the value of a diverse collection. It goes without saying that decent accommodation should be given for everything.
Where I would (hesitantly) criticise Berlin is that it doesn't seem to be maximising the benefits of the Tierpark's size. The cats in the Brehm house could very easily be given good homes in some of the underused wooodland, for example.
And some of the ungulates in the West really should be moved East to make space in the former - again, many of the cats in the West's Carnivore House are living in conditions that are 50 years out of date - in a house built in 1975!!