I like the idea, TC, but those choices were pretty bad.
Lu Bu is probably the biggest name. Tadakatsu is like the Lu Bu of Samurai Warriors. But I think, representing Warriors Orochi particularly, should be someone original to the game (so not Xiao Qiao), but also someone important (so no San Zang or Himiko).
Someone like Taigong Wang, Kaguya, Susano'o, Shuten Doji, or Orochi would be good. Nice and strong, somewhat unique, and heavily prevalent in Warriors Orochi 3, particularly. Orochi would probably be the best choice. I mean, Ne Zha, Kiyomori, Da Ji, and Wukong aren't really big enough.