Fiora's passive
So, something I thought was weird was that it's oriented in a horizontal+vertical fashion. In lane, this can either present you with an opportunity to hit one of the two potential Vital spots facing you, because you're generally in a diagonal positioning relative to your opponent, but it also makes it difficult to spot and proc the northern one.
I think that changing it to a diagonal orientation could improve functionality, and make it easier to proc.
But it would also be a simple fix to compensate for the lack of access to the "back" region by having Lunge proc the Vital spot and land you on that side of the opponent.