I think you have pretty much hit the nail on the head. The good elders no longer want to be elders due to the politics of the watchtower, leaving this wide open for the many narcissistic sociopaths becoming elders.
Pioneers can also be a funny lot too, some think they are a cut above the rest and make it known by mistreating others but get away with it. Again, as above, the narcissist has a field day.
You pretty much described the KH I was in. There are people in KH that would actually drive you out due to their vindictive behavior! Because the number of people who have privileges within a KH is dropping at an alarming rate, the org is desperate to plug the hole. It's got to the point where they don't care who is appointed, just as long as they follow the watchtower line, anything else is secondary. That includes the mistreatment of so many good people still trapped in this cult!