Melbourne currently have two males so would require either transferring out their current pair or expanding their exhibit to accommodate the males.I totally agree with you, best case scenario would include the two boys moving to another facility(in my opinion Melbourne) and having the girls stay along with Ato and Maya as Taronga just doesn’t have the space required for another litter. In the originally proposed plan there was two seperate exhibits, one at the wooden shade structure and one at the current backstage behind the main viewing point. Had Taronga gone ahead with these plans there could have been a conversation around holding two litters, or at the very least a seperate male enclosure like the Congo Gorilla area proposes.
As for the Tigers, I personally enjoy having all the cubs roaming around with their parents, it makes for a pretty special encounter. I can never seem to remember, is there 3 or 4 cubs? They move around so much—luckily— that I can’t count them regularly, especially with the thick foliage covering most of the outer exhibit layer. It would make most sense to keep them there until their parents eventually pass away and then maybe look at renovating the precinct to give them more room or bring in a breeding pair to accomodate them.
Taronga does actually have the two exhibits, which is presumably what they utilise when separating the pride up. A second litter is certainly not on the cards especially with; a) Maya being almost post reproductive (if not already) and b) the current cubs not being genetically valuable.
Re. the tiger cubs, they're usually kept with their mother (Kartika) as @Osedax said, but occasionally are now displayed separate from her on occasions. It could still be another seven years or so at least until the cubs current parents pass on, so it would probably be advisable to bring in a mate for one of the cubs prior to that if there is the intention of breeding. That *would* probably require them moving some of the tigers out. Dubbo have three ageing individuals, so would probably have space to acquire the remaining pair of the cubs. Therefore it would probably be best to use the male (Pemanah) as the breeding male and send his two sisters across to Dubbo when the time comes.