One major insight I got from the Divine Purpose book was that a major effort by the organization was to solve the military service problem. They just had to have a way to establish with the courts that a JW service-age man was a 'minister' and qualified for the ministry exemption. Post WW2, they made a number of changes to support this effort:
Changed 'all religion is bad' to 'true religion and false religion', due to criticism that to be a minister one has to be a member of a religion.
Introduced the Ministry School, at first entirely for men (because of the draft) to answer criticism that JWs had no training to be ministers. The textbook was 'Qualified to be Ministers', the 1950's edition even had a list of JWs by name who they identified as ministers.
Gilead school created to provide an answer that their ministers sent overseas had theological education equivalent to other religions' schools.
'Pioneer' status invented, replaced the culporter, which was argued to be simply a salesman. Pioneers had strict rules about counting and reporting hours in ministry.
All these changes described in the book were initiated entirely in the context of supporting their stance against the draft. The court win in the 1954 Walsh case (Scotland) was touted in the book as a victory.
'Our Kingdom Ministry' introduced to support the fiction that the Ministry School had a curriculum