LotusRayne:
I could really picture Tan Jian Ci being very good as Yan Bing Yun based on his Cao Pi from Secret of Three Kingdoms or Sima Zhao from Advisor's Alliance/ Crouching Tiger, Roaring Dragon.
But I wouldn't really be adverse to Xu Kai either, he did very, very well in Story of Yanxi Palace and would fit the role nicely IMO.
Tan Jian Ci sounds like an awesome idea!! Albeit he has around 4 dramas coming this year, and JOL2 is already slated for coming out this year. If a name like him was joining they would have sent casting calls and extended the olive branch in advance. :'(
Between TJC and XK look wise though I feel like Xu Kai would be better for the YBY part. I've watched TJC alot and although between him and XK he has better experience and credentials, Xu Kai being serious (his serious roles like The Story of Yanxi Palace, Royal Feast) would drive home YBY to me. He has that aura.