Please accept my blessings. Hope you are well. I am so much pleased that you are studying seriously our Krishna Consciousness philosophy. Please continue with your sincere efforts for Krishna. Now, regarding your question about Brahma, he may be chosen either from the liberated or the conditioned souls. In this case Brahma is a liberated soul from the beginning; therefore there is no contradiction that Brahma can be Haridas Thakur. Those who are conditioned souls are eternally so, which means that it is never possible to trace out how long ago the conditioned existence began. We simply say that misuse of the little independence we have got creates so much trouble for us. But now by adopting Krishna Consciousness, we may finish this conditioned life immediately. That is Krishna Consciousness.
Your reasoning is all right that the Brahma energy must have conscious direction to manifest form. Therefore He who gives that direction is the Ultimate Controller or Param Iswara. In Brahma Samhita it is said: "Isvarah Paramah Krishnah sachchidanandavigrahah, anadiradirgovindah sarvvakaranakaranam." Krishna is the Supreme Controller of all controllers and therefore, He is the Origin of everything including the Brahma Energy. This Govinda is the cause of all causes, and He is without any cause. This is the beauty of the Shastras, that one sloka finishes billions of years hard labor of mental speculation. Just try to give evidence like this.