It does not take years. I cannot engage in polemical writing. It would taint what I hope is an honest and even handed approach to history.
Thinking is physically painful. Truly. It swells your brain cells. Ever hear someone say, "This is giving me a headache"? But ... you can do this. My suggestion is that you watch some of the youtube videos on formal logic and logic flaws. They will teach you how to reason. Good writing comes from sound reasoning. It's not hard to learn but it does take persistence.
I did not answer a previous comment. You suggested that if they were wrong in the past, might they not be now. Yes, of course. But that's the course of human reasoning, of human learning. So the issue is: are they wrong now? If so, prove it. One of the great flaws of opposition writing is that much of it simply restates 'orthodox' belief. Because it is 'orthodox', then every view in conflict must be wrong. This is one of the major logic flaws. And historically we find Jesus and the passage of time correcting the apostles' false views. Merely changing what we believe is not a sign of flawed belief; it's a sign of intellectual activity.
You do realize that every major religion, those often seen as orthodox had a doctrinal development that included changed views, what some here call 'flip flops.' So get down to a single point. Do you object to Witness anti-Trinitarianism? Is Jesus God? Are they wrong about John 1:1? If so, say so and prove it. But be prepared for a response you may not be able to handle without solid research. For instance, Why does John say Jesus was God instead of is God? How does this connect with a later verse that says Jesus became flesh? Does the Greek word for 'flesh' identify him as a person or does it identify his nature? Witnesses will ask you these questions and rightly so because if flesh identifies his nature then so does the anarthrous theos. There ARE Witnesses competent enough to present you with this argument.
Right now you simply believe Witness theology is wrong. Next you must prove it to yourself. Belief is not proof. Tracts such as you envision work best if they are narrowly focused. Pick an issue, explore it fully. Ask yourself if your 'proofs' could convince you. Try it out on a Witness friend, especially one well versed in their belief system.
Do you object to the Witness concept of a Governing Body and the application of the Faithful Servant parable to it? There are a multitude of differing conclusions about the Faithful Servant parable. In the 18th and 19th Centuries, Clergy saw that as fulfilled in themselves. That's not much different than the Witness view. There are three approaches to church governance that find a home within Christian churches. Do you know what they are? Are any of them similar to Witness belief?Are any of them scriptural?
You can learn grammar and spelling on the fly. But research is hard work. You must do your research if you wish to succeed. Volume 1 of our current book was written between 2007 and 2014. It required a huge amount of research. You're not writing anything like that. Not if you pick a single subject and write a pithy, well-researched rebuttal of Watchtower belief.