Of course, it was a way to close the Spock's chapter and a way to promote both TNG and Star Trek VI.
I suppose the Spock's movement has two goals, the cultural one and the political one.
It was a good way for Spock to promote Vulcan culture. Spock hoped that Romulans and Vulcans will be again the same people, but he was conscious that he will be long dead at this time. Whant he could do, it's create a fraternal links between this people. This new brotherhood would help to spread Vulcan cultures into Romulan empire.
This new brotherhood would also allow a durable peace between the Federation and the Romulan empire and reform the Romulan regime. Probably there was some officers deeplyinterested by Vulcan culture, but I think those military leaders were mainly reformers. N'Vek was definitely not interested by the Vulcain way of life. He was more like Toreth.