I like the possibility of "Ollie the olingo" or "potto pot noodles"
Maybe it is indeed innate to humans, this fascination with big cats and megafauna.
There was that study (was it E.O. Wilson?) that proposed that we like open spaces and lawns precisely due to our evolutionary history in the African grasslands so perhaps there is something similarly innate at work with large African (and what were once European too) species ?
When you think about it, the caves of Chauvet and Lascaux are testament to the fascination and reverence that Magdalenian era hunter-gatherer humans had for lions and bears and hoofstock.
However, all that considered and granted, I do not personally like a zoo to develop excessively along those lines for obvious ex-situ conservation based reasons.
Perhaps the best alternative (which I believe you are hinting at Andrew) is a few "charismatics" and many species of conservation concern which is arguably what Bristol had anyway with their gorillas and lions.
Longlive the Jersey spectacled bears, gorillas and orangutangs then ! (meerkats and Asian short clawed otters a different matter though ! ).