Korean actors as Mystic Messenger characters

I was wondering it would be great if Mystic Messenger got turned into a K-Drama since it's a Korean app and with so many routes, I believe there are multiple ways it could be represented. However, then I also go into thinking who would act who, so I made a list of characters. 

MC (Kim So Hyun):

Rika (Yoona):

Jaehee Kang (Go Joon Hee):

Yoosung Kim (Taehyung):

Zen (Lee Jong Suk):

Jumin Han (Yoon Hyun Min):

Saeyoung Choi (Lee Hyun Woo):

Saeran Choi (Lee Hyun Woo):

Vanderwood (Jang Keun Suk):

V (Hyun Bin):