Welcome to the forum from Texas. This is a great place to get questions answered.
Your jacket is beautiful. If it were me, I would use a band to face the entire neck (front & back) & I would go ahead & face it all the way down the front to the bottom edge on both sides. Looks like you've made great progress in making this without any sort of instructions & I think you will be pleased & proud to wear it when it is finished. Don't forget to show us the finished jacket.