The themes aspect would be cool, but not a major must have. But seriously Apple really needs to revamp the Notification system from the ground up, that's something that really needs to be worked on A.S.A.P. I am shocked iOS 11 didn't have a major Notification system revamp, how can people not realize it sucks ? Again not saying they should copy Android's, but come up with something better than pile of smelly dog poo that iOS notifications are.
This is exactly what I am talking about. I don't even understand this myself. I have no issue with notifications on either system and don't even understand what you mean . Both phones notify me of something coming in. Do I know when I get a text, call, email, or app notification? Yes. That is really all I need. Trying to figure out what else someone might want.