If you play by their rules, they win. Their rules are designed to protect their flock from you. Officially disassociating puts out a warning to all JWs not to listen to anything you have to say. Even more importantly, it warns them not to answer your questions.
All of your JW life, they have been warning you and your friends and family, not to listen to apostate reasoning. What makes you think that your family are different, and will listen to you? especially once you have your Apostate hat on?
Instead of telling them what you think, make them think. Ask them sincere questions, one at a time, that they think/pretend/boast they should be able answer. Make them do the research and the reasoning and put them on a guilt trip if they try to weasel their way out of it, or use any kind of psychological warfare to get you accept illogical answers.