Sometimes when someone posts a question for advice, there are missing aspect that skew how the situation is perceived. After 20 years of full-time music ministry, I have found that churches have varied histories. Anything you wish to address must be dealt with separately. You also have to identify your leaders. By leaders, I mean those who have influence in the choir. Rally them on your team, and they will bring the choir along. If uniforms are an issue, then I would consider finding out why they were implemented and see if a new protocol can be set. I think sometimes we forget that any disturbances in the choir are usually not related to the matter, but something deeper. I also don't just jump to the conclusion that "devil" is trying to divide us. Many times someone(s) feel insignificant or overlooked. We have to have the wisdom to let them know they are heard and that they matter. This doesn't mean doing what they want all the time. It may mean speaking with them or taking them to lunch or something just for fun. That positive attention often helps them to come back more pleasantly.
I don't like having non-musical discussions during choir rehearsals because it takes away from the purpose of being there, especially as people start all talking. I encourage you to consider two or three choir fellowships during the year where the next seasons vision is cast, the plan for the next major event, and even talk about issues. Because people are eating and playing some fun musical games, it's less tense. I have done this over the years and found it to be the most effective way to hear from my choir without having a "meeting".
