It is indeed a great setup overall. Tree kangaroo and kowari exhibits could have been bigger, but overall it is very well designed and especially the koala enclosures are something else compared to the general way of displaying them.
@MRJ Based on the earlier discussion on faithful koala enclosures. The one in the Wilhelma Stuttgart is botanically based on Noosa NP, just north of Brisbane. They imported seeds from over 60 plants species occuring there directly from Australia. Apart from several Eucalypts it includes Banksia, Xanthorrhoea and Brachychiton. This picture shows the viewing area, below is a link to one of the koala enclosures. The Wilhelma being a botanical garden too will certainly have helped in the planning stages, which is also reflected in their koala diet, which apart from imported eucalypt features 37 eucalypt species grown in their own greenhouse.
Fascinating stuff. Glad to see some attention to detail for an overseas Australian exhibit. Looking at images of this display, it does mirror some of the wet forest habitat types at Noosa NP that it has further away from the coast having visited a couple of weeks ago. Banksias and grass trees (which are in bloom at the moment) are particularly prominent there which they have modelled nicely.