Well..you asked if Buddhism is a theistic or atheistic religion. Theism and atheism are western concepts related to the concept of "theos". Can such a question come up in the Indian context...no. Therefore if you ask a question that is tied to Western conceptions of God, then you will get answers related to the same, is it not?Forget the west. The west is irrelevant. Forget about translations also in that case. Just address the phrases I have given you. In the Pali language. Forget the English translation. Explain what they mean then. K?
dhikkhena, Deva, Yamaka, Brahma, Brahmanang. Are they all aliens? Just out of curiosity. Is that how you explain? No problem. SO they are alien beings. Do they have powers humans don't have? So bottomline is, you do say that Buddhism is not an atheistic philosophy, and you do say that there are other beings in different plains or Bhava's. Okay. No problem. I was looking for your view clearly. I never referred to this "western" God.
That's quite close really. Sahampathi means "the ruler of all" in simple terms. Congregation leader would be Sabhapathi. A much junior position, but close.
Does Buddhism has devas and Brahmas. Yes. Does it have God(s)...that depends on what makes some entity a God and what concept you are bringing with you about God.