Nautilus is bad because he cannot carry a game by himself.
All he can do is provide other people with kills. He has no damage that he himself can do because riot removed most of it through various nerfs. Why play a champion that can only enable other champions to do well? Oh? What's that? Is that called a support? Well we already have one of those you say? Well fuck me.
Sarcasm aside. Nautilus needs his damage back, or you should buff the CC effect on his Riptide to be more inline to the Cinematic. It's great nautilus can gank really well. But that's all he can do. What's going to happen once the laning phase ends? He's got no damage. Long duration's on his CC's. He's like a weak version of thresh in a way.
I would like to see Nautilus be more damage heavy so he can exert some actual pressure.