Not paedophilia - as much as that must be dealt with. Not blood, shunning, corruption, failed prophecy, bunked chronology, the Internet or U.N type scandals.
The biggest issue/threat the watchtower faces is AUTHORITY.
Hold up any other issue before a true JW and the shutters come down. Why? Because they have listened to 'authority'. Try to reason with them from the Scriptures or by logic and your arguments will be politely dismissed because you do not speak with 'authority'. This all changes - gradually - when the authority of the Governing Body/Faithful and Discreet Slave Class becomes undermined.
If they they do not have authority from Jehovah God then everything else begins to fall away, including the scales from their eyes. For good reason, the Society constantly warns the brothers not to allow apostates to plant a seed of doubt in their minds, to 'watch out for the [corrupting] leaven of the Pharisees'. I say, let's do what is expected of us. Plant those seeds of doubt about the 'Slave Class'. Share the corrupting leaven of sound scriptural refutation (if that's what you're into) or clear, simple logic and reasonable argumentation.
You are an Apostate, be proud of it!
Nic'