Ruby I think you are correct JWs are very different from the Moonies and no where near as bad judging by his experience. The problem with lumping all such groups together is it can seem as if they are all the same. JWs do not engage in sleep deprivation or group confessions and blackmail or sex with cult leaders or any of the more extreme cult behaviour.
What they do on a massive scale is information control, shunning and stigmatisation. These are harmful practices that Hassan fairly highlights in relation to JWs.
I agree that Hassan's book is not ideal for JWs because an intervention type scenario (he promotes a milder, "strategic" form of this now) is not terribly appropriate for JWs.
Unlike many cult groups, I think the uncomfortable fact (for some angry former JWs) is that many JWs are very happy as JWs and they function well in normal society. Do such people need to be rescued? You could argue they believe nonsense and they could do better in life. But that's true of many people. It's no warrant to go meddling in their lives.
On the other hand many people suffer as JWs for various reasons and could do with a helping hand out of the organisation. Reaching and helping those ones, without harassing the many JWs who are happy as they are, is bound to be a tremendous challenge for any sort of activist interested in thoughtful engagment.