I'd be pretty amazed if we got the bond-crystals at all. It's not really compatible with the "Micro"Transaction model used in Nutaku FKG.
It would definitely improve the game, and might attract more players. However, most new (or, returning, for that matter) players would come from other Nutaku games, like, Kahime Project. And cannibalizing one flagship to slightly improve another is not smart business I think.

Even cannibalizing their "smaller" games in favour of one of the flagships wouldn't be smart: lots of players play either FKG or Kahime with one "small" game on the side. People purchase NGold for their account in the flagship game, however, they're also strongly incentivised to invest the remainder, or left overs of their NGold in the side-game they play.