Australian zoo visits/tour

Hi everyone. Just trying to think of an anniversary idea for my husband and I. We will have been married 21 years in June. We both love animals and zoos. I was thinking we could do a zoo tour (flying from place to place). Has anyone tried this before, and /or does anyone have any good ideas of how to actually do this well? Considering how much I love zoos, there are several in Aus that we haven’t been to. I’ve been to Sydney (thats where we grew up), Canberra, Steve Irwin’s zoo, hunter valley (surprisingly good), featherdale, and I think maybe Adelaide when I was a kid (but it doesn’t count because I can’t remember). Or maybe we should just do a week or so trip to NZ… that’s where we went for our honeymoon way back when… Thanks for any thoughts/ ideas you might have good people!