Sion needs one pretty bad. If Creative at Riot hates one-dimensional characters then they must really hate zero-dimensional characters like Sion. Also maybe the remake can better explain Sion's magic powers. I don't really have a problem with the cognitive dissonance with Sion's visual/gameplay design but clarity would maybe add some character.

Who else do you think needs a remake?

Jayce, Syndra, WW, Soraka, Kat. :3

don't be a smart-ass sleepy >_>

Although, I do agree with Syndra. Sivir, also.

Sejuani needs a remake.

Sion might too.

Sion and Nidalee need a graphics boost.

Tristana and Annie are the first two that come to my mind. Not much about them other than their reputations and relations.