Well, in the second commandment, “thou shalt have no other gods before me,” the Hebrew word for “gods” is elohim, and that is a word that is capable of a variety of meanings. Generically, it refers to authority. It was used by the Psalmist in reference to Jewish leaders who were mere humans. It is also used of angelic beings. So getting that it is talking about dieties per se is a matter of context.
For example, that command is immediately followed with a command to not build physical idols for the worship of these other “elohim.” Are they real? The passage neither confirms nor denies their reality. But it does affirm they shall not be worshipped.
So flash forward to Paul in 1 Corinthians 10, where he says that idols represent devils. Here we have fallen angelic beings being worshipped, who do try to exert authority over human souls, but who are powerless in the presence of Jesus. Satan is called the god of this world, but he too is a mere angelic being, fallen from his once high place, and doomed to eternal failure.
But I think even more generically, mere things or objects with no supernatural aspect can become false gods. Mammon, for example, which represents the worship of material gain. So really, a false god can be any being or any concept that asserts itself as the supreme governing authority of one’s life apart from the true God.
So no, I don’t think the Bible supports the idea that there are good but lesser deities. Bad beings, false ideals, but no good guy hammer-wielding Thors. Good angels, yes, but they would never presume to themselves the title of deity. For the Christian, there is but one Deity:
Isa 43:10 Ye are my witnesses, saith the LORD, and my servant whom I have chosen: that ye may know and believe me, and understand that I am he: before me there was no God formed, neither shall there be after me.
That was really a great reply; very concise. Thank you!