My guess is the format (including Big Bang, I think) will remain intact, but the bonus round is simply attached.
Honestly, if I were to attach a Bonus Game to PYL, especially if there were a syndicated version, I'd have an "eliminate the Whammy" game, whereby eliminating 10 Whammies wins a bonus prize, such as a car. (Or, if this were the 1980s version, maybe $10,000 cash.)
Here, the game would begin with a set number of Whammies on the board, the idea being you want to land on the Whammy. Each time the contestant lands on a Whammy, it would be worth cash (in the 1980s, it would be $100 per Whammy landed on) and would take that Whammy space out of play. The contestant would get one miss, but a second miss would end the game with only the consolation cash. However, landing on a 10th Whammy would net the bonus.
It'll be interesting to see what the bonus game will be here with the ABC revival.
Brian