Few changes to Fiora
A) If you are going to give her the strongest AoE heal the game has to a FIGHTER, and give us the "it's because she inspire her teammates" as an excuse to that, then stick to it. If she dies then the debuff from the target disapears, so that she cant just mark someone and their team mates blow them up and still get the heal. And if someone who is not her gets the kill, either the heal doesnt go off, it's a weaker heal.
B) If she's going to proc her ult from killing someone with revive, then make every other skill that resets on kill do the same CONSTENCY, you said that was one of your design values, stay true to your word.