First, use this link and search:
https://en.wikipedia.org/wiki/List_of_highest-grossing_media_franchises
Second, they ARE good options as characters, but not as creative ones.
Lloyd is a character who doesn't have much to offer that characters like Hero, Link and Marth are already using in the game. Other game characters in his series are more creative than him ( Mikleo, Velvet, etc ).
Heihachi is a fighter who will only use punches and kicks. He is basically a Ryu who doesn't use special attacks. Other game characters in his series are more creative than him ( Jin, Kazuya, etc ).
I'm just saying Bandai Namco has other more creative characters to use. Like Klonoa, KOS-MOS, Prince of Cosmos, Agumon, Don Wada, etc.