Life doesn't work that way. And you don't get to decide when another parent gets to go out and "have fun".
Though I am not suggesting you don't have one, if both of you are agreeable to it, what I am saying is if you do, it needs to be more concrete to be enforceable.
BUT, what he wants may not be what YOU want. He may want one that allows your household members to babysit, or have it be if your absence is over 24 hours, etc.....
You need to think about what type of ROFR limits will be acceptable to you, and what you would be willing to settle for.