Rotational Exhibits
With zoos in the region like Perth planning to construct rotational exhibits to compensate for the lack of space available in city zoos, it'll be interesting to see if Melbourne undertake this.
The elephant exhibits that will soon be vacated could be remodeled as a shared zone for Sumatran tiger, a second carnivore such as Sri Lankan leopard; and an ungulate primate combination that would rotate use of the exhibit.
Aside from the stimuli this would bring to the species involved, visitors would benefit from seeing something different on every visit.
It would also free up the second Sumatran tiger exhibit in the Carnivores precinct, allowing this to be redeveloped and used for either a new species or to afford an existing species more room.