The GB on K just means she has a different poke option than the standard PP string most use as a whiff punisher.
It's nothing too substantial, since +2 still leaves all of her options (high, mid and low) slower than most everyone else's options except for her P+K.
It's not that it's bad or worthless, just not the best thing she was given. The PPP buff, increased launch height on Hiten PK and Hiten 2K bounding will all have a more noticeable impact on her gameplay.
logically true, but there is a certain panic and frustration aspect to constant GBs. mentally it just grates on the opponents nerves causing them to make mistakes.