I just had an idea for a setting I would definitely use if implemented! I was thinking about how I never use the one "automatically release un-named pets" setting when I had an idea. What if you could mark which pets you wanted automatically released and which ones you wanted to go to your stables? It'd be a sort of mark that you could turn on/off with just a click, so if you put the mark on a hatchling you think you won't want, and then it becomes an adolescent and reveals a trait that makes you change your mind, it's an easy switch. And vice-versa.

This sounds like a great idea, to be honest :D