Hello!
You may have already been told but all gliders have their own personality so what the Joeys do is random. I have gone through two liters with my gliders and knock on wood I have had no issues with joeys trying to climb out. Normally the joeys will stay in the nesting area for a couple weeks and only come or on mom or dad. These babies have an amazing grip like their parents do even at such a young age. I would not be to concerned about the babies falling out our climbing out of the area. It seems that even if they do on done rarity that you seem to already have something soft food then to land on with all the hammocks. As from limiting where the babies can be, mom will normally keep them together and not move them around but you might want to give mom options on where get babies do sleep. Youdon't really need to change anything on your cage . Just make sure that your able to get to the baby top check on him in case of an emergency. You can switch pouches when you need to what you can do it when you want to stick put the clean one in the cage and if mom and dad are out playing just switch the babies to the new one with a scented piece of fleece. I was able to do this with my babies and I had no problems. Mom will find her babies
Just keep an eye on the since they are not his but he should take care of them like his own. How everything works out well!!