my guess:
Guo Jing - definitely not the fire signs, maybe water or earth sign, i am guessing either Capricorn or Cancer
Huang Rong - maybe a Gemini or Aquarius
Mu Nian Ci - Picses
Yang Kang - definitly a Gemini
Huang Yao Shi - uh.... for his erratic characters, i really can't find a sign for him, but he's tempered, so maybe Aries
Zhou Bo Tong - Libra
Ou Yang Feng - both him and ouyangker remind me of snake or scorpion, those kind of animals, so i would guess Scorpio for him, he is very ambitious and evil, i don't mean scopios are evil, no offense
Hong 7 Gong - Aquarius or Libra
Zhang Wuji - Taurus
Zhao Min - Gemini or Leo?
Zhou Zhiruo - Scorpio
Xiao Zhao - Cancer or Virgo
Yang Guo - Gemini
Xiao Long Nu - dont' know,, maybe Capricorn?