Giving the opportunity to replace hindrances that just never get used is a good idea. Stuff like that happened at our table and I thought that the players would go after they needed the bennies, but treating Bennies like a “hard” resource doesn’t work so well.
However, I don’t share your dislike for vengeful. Sure, it can be mighty annoying, but many of the roleplaying hindrances can be. Heroic characters, for example, – especially when they additionally have stubborn – can be a big burden for the whole group, but also a great lead to get the adventure rolling. Same goes for vengeful in my opinion.