I think Jhin should back to the drawing board. Here's why.

With his lack of mobility and huge focus on planning and damage-over-time, I feel like he is in a position that is very different from the traditional adcarry and is therefore limited by the intention to put him in the bot lane. I feel he would be a better, stronger character if he was expressly designed as a Top or Mid lane marksman, with no kit design intended for bot lane. He would be in a better spot design-wise.

He is being limited by the intention to be a bot lane character.