I had the same issue with FIFA 16 and 17—great games, but too easy. Eventually, through trial and error—using a mix of mods and extreme slider settings—I managed to make matches more challenging and ensure the CPU scores more goals. I’m currently playing one of my toughest seasons in FIFA 17; I have to work hard for every goal. I increased the difficulty level but lose a bit of realism, but I can live with that.However, in both '16 and '17, the problem remains that when playing against giants or top-tier teams, you generally don't feel the difference on the pitch.