The truth is that this is not a locution. It is perfectly understood , even if it lacks more than just a context; like being between exclamation points (" I wouldn't miss more!" ) and then it is used to complain about an order or an abusive situation, as if something worse might appear on top of it; or if they omitted a comma ("No, I would miss more") to respond to a thank you, as if to say "don't thank me, I should do more for you".
