Idea: For a big title fight you get the option to go on an expensive training camp.
Pro’s: increases the chances of the boxers stats improving in some way (but not guaranteed)
Cons: very expensive. Perhaps it could half the fight profit or something like that. Not guaranteed to work re improving stats.
I would suggest you only get the option to do it when you hold the WBC. Their timeline for title fights makes sense for a training camp. And it would give an incentive to hold the most prestigious and hardest to defend belt.