Fiora just needs her W to reflect damage+status effect. She scales just fine atm.
Maybe a slight cd reduction on her early level Q.
It's the fact that she's a glass cannon that holds her back, it has no real place in the current meta. Bruisers and AD assassins are stacking defensive items and still wreck house, Fiora can't do that. --- Going to church doesn't make you a Christian any more than standing in a garage makes you a car.
AD Melee carries are misfits of the current meta, that's why we're seeing AP Yi and AP Trynd out there. At least the latter two has some sort of sustainability, whereas Fiora really needs those Vamp scepters to fully sustain herself. --- This is a signature.