How are you finding IOS now ?, The only notification problem i had moving to ios from a Samsung phone was Gmail. But from help from the forums here. i was told ios does not natively push Gmail emails to the notification center. once i realized this was installed the Gmail app was golden.
I find the way ios deals with notifications far better than android.
The most recent notification you receive is on the top of the list. in android its not they are mixed.
Just like an android. you can tap on the individual notification and reply within the notification( a lot of people think you cannot do this and always put that as a negative)
Grouping of notifications is just as good if not better than android.(again people think ios cannot do this)
Sticky notications.
All in all for me and my use the notification system of ios is better than android.
The only things i miss from android is the notifications on the Aod and notification light( both the one you can use the camera lense for and the ones from goodlock)