Her best follow ups after these is whatever you choose. Following up with something quick and safe is ideal but it's whatever you want to do. There's no right, wrong, or best answer here. Since this damn game is almost 100% guessing and requires heavy reading of your opponents. You'll never know what to do after being at a +. Player A may not like to hit buttons on Monday but they may like to hit them on Thursday. Theres no way to link these moves safely for many reasons. So strategies constantly change and this may sound complicated to many. Though in reality it is not because we play DOA.
So your strategies after doing a move leaving you at + with Pai should be: throwing for players who block or are hold happy or a simple Jab, 6P, or 2P for players who like to hit the buttons. Even still these are not solid strats until you read what type of player you're up against. If you're not doing one of these 2 strats, it's cool, just do whatever your heart tells you to do on that day.
Your aim is to get a stun with her or her throw follow ups in the first place.
Pai's BT9K gives her +3 or 4 depending on what you do to get to the move.