Given that your cs per minute is usually < 6, you need to focus on last hitting more and not letting your cs drop off after lane.
Given your high KDAs and abysmal winrate (sorry but it's true) it seems you put very little emphasis on using your lead effectively to snowball your team and close out games before you throw.
im aware of my winrate, but i actually disagree with blaming it on my ability to close out games. i actually consider myself a good team leader (for my ELO) and always focus objectives. the problem is ive been having so many run ins with early game feeders, trolls, AFKers, and autofilled supports, that the game is just REALLY hard to win when that is happening and youre just having an average game yourself
here is my most recent game lol
but who cares its the pre season
its the worst feeling though when youre confident you can win any botlane youre up against but your support has a whole nother plan about that one