The simplest way to improve Fiora's gameplay
Fiora's new ultimate (Grand Challenge) reveals four weak points on the enemy she targets as well as creates a zone around them which gives Fiora bonus movement speed. Fiora would feel a lot more rewarding to players who don't like her update if the zone which gives movement speed had a smaller circle inside of it showing how close Fiora needs to be for her Q to land on a weak point.
Too many times have I seen Fioras try to dash to their ulted target only to come away with much longer cooldown on their Q. Having played Fiora quite a lot myself, I feel like this change alone would make her so much more appealing.