I would have agreed with you about Ngakoue before I saw him this year. I was disappointed.
I was very disappointed as well. But, I kind of give him some leeway. He came in halfway through the season, to a very complicated defensive system. I mean, Wink was smart and pretty much only threw him out there to go after the QB.
From what I saw he relied way too much on straight speed rush moves. If he could develop a Freeneyesque inside/power counter off of his speed rush, he could be downright nasty.