I'm just so eager to show him what I'm learning that maybe I'm not going about it in the right way.
A word of caution.
You haven't even finished reading Hassans book yet, and already you are trying move for change. You may be missing very important points if you rush this process. For instance, the most important thing about fear is that it is used to coerce people into making decisions that they normally would not make otherwise. Walking people through examples of how this works in other groups, as well as the group under discussion is one way this can be articulated to the "high control group" member.
Additionally, the idea of focusing on other organizations that have similiar teachings lays the groundwork for a conversational dead end. This is because the argument impliciltly suggests that the Watchtower's institutional and doctrnal structure has legitimacy. If your husband actually does begin to look at those other groups he will no doubt find a reason to say they are not "the truth", ending the discussion. Don't paint yourself into a corner if you don't have to.
Take a deep breath, relax, and be glad that your husband isn't getting ready for a divorce. No doubt he shares some of your feelings, but has not come as far as you have....yet.