So, no complaints about the new Fizz update, personally I think that his changes make him all around better, for both his players and his opponents. There is one issue, though, that also applied to him before the rework, and that is the huge hitbox dissonance on his ult, which makes it hard to determine exactly where to aim and how to dodge it.
My suggestion is that instead of throwing a fish, he could stab the ground with his trident, causing a school of leaping fish (or a shark's dorsal fin) to appear swimming "through" the ground, leaving a wake of splashes behind it that corresponds to the actual hitbox. In addition to being more healthy gameplay-wise, it would look cooler and fit with his whole "trident magic turns the ground into water" theme.
Also, before the shark surfaces, a bunch of splashing, jumping fish can appear jumping out of the ground in the area where it is about to pop up instead of the rather silly-looking fish circling in the air.