Imagine that a Jew were to say the following:
I believe in the Greek sun god Helios. I believe that he is real, is a god, and has power. However, I believe Helios was created by, and is subservient to, Hashem. I also believe that Helios' power is dependent upon Hashem, and can be revoked or removed at Hashem's will at any moment. I do not worship Helios, I just believe he exists.
As far as I can tell, this belief, while rather nontraditional, is not in fact at odds with Judaism or halakha. I would even go so far as to say it ultimately comes down to semantics - if god is defined as "The singular being with complete and absolute power, ineffable, that which always was and always will be, and Who created everything and is everything", then it follows that there could only be one such being, and that is Hashem. If we instead define the word "god" as "someone or something really big or really strong, with capability that dwarfs any normal human, but not necessarily infinite in scale", then I think it is not, strictly speaking, "un-Jewish" to say that multiple beings fit that criteria provided that we recognize their subservience to/inferiority relative to Hashem, from whom all other beings descend. Indeed, by that definition it could be said that Gabriel, the Leviathan, or even Og, are, in some sense of the word, "gods", but much smaller/limited in scope and scale/undeserving of worship/otherwise total squares compared to Hashem.
Is my reasoning correct, or is there a clear prohibition against ever acknowledging any validity of another deity, no matter how it is justified or downplayed?
Note: I use Helios as an example because there are a handful of cases in which synagogues of the ancient world contained pictures of Helios or other references to him, making Helios a genuine comparison. The prevailing scholarly theory is that these synagogues were not heretical Jewish groups who believed in Helios as an independent deity per se, but rather began to consider the gods of the surrounding nations to be angels while not actually worshiping them. My question is inspired by that, and essentially asks whether such a thing or its logical extension is possible/halakhically permissible.
Update: I'll note that the first and second of the ten commandments are "I am the Lord your God", and "You shall have no other gods before me". As far as I can tell, this could mean "I am your God, and the other godlike beings are not your God, even if they could be defined as a god by some definitions", and "You shall have no other gods before/above me, or receiving worship, but not necessarily after me [in the manner I described two paragraphs above]".
Also, to be clear, I do not believe in Helios or any other such thing, but I still think it's an interesting question.