Ollies cage is 30x24, he only ever flies back and forth in the longest direction, he tends to climb round or hop onto a toy/perch to cross in the shortest direction. Even if he did fly he wouldn't get more than a couple of wing flaps in. Harlies cage (cockatiel) is too small for her imo and is only just smaller than the 24x24 one you have and she is only slightly bigger than ollie. She couldn't possibly fly in it, that makes me sad but she frightens to easily and wont have a sleep cage so its for her own safety atm. She can come out her cage almost all day every day though.
I've no idea why you thought the cage was too big, for a caged smaller species of conure I would say it was a good size, even bigger would be even more ideal
