riven and fiora too op

In my opinnion fiora and riven are too op. it isn't that they hit hard or that but when they tower dive me when i'm full hp. they are wayyy too easy and still so op. I think riot should nerf fiora and riven really good. if full hp riven comes under our turret and kills our full hp garen I think she is little bit too op. And I also wish that you could hit fiora while she is ulting. and when riven is little fed she can just bounce to you and stun you for 2 seconds and after that she can just hit you till you die. plz help me to get riot nerf riven and fiora (mainly riven).