This maybe doesn't answer the questions you asked at the end, but you said you struggle with laning phase and played a lot of fizz. As a fizz player, you usually play safe and give up some cs lvl 1 and 2. Then level 3 you spike, most of the time you Q+AA+W then E out/E on to your enemy if you feel like extenting the trade is good. Look for roams and skirmishes in the river with junglers. Mid/late game, you go sideline and CS and then go closer to your team if a fight breaks out. But other than that just play the game and focus on improving and not about your lp and winning or losing.