The powers of darkness are still part of the spiritual world - they don't become something else when they rebel against God. Disembodied believers are, by definition, also part of the spiritual world. So are God and Christ.

We like to pretend the core ideas of the faith are more palatable or workable within our modern rationalistic approach to Scripture than the stuff we want to call "too weird" because of our own intellectual sensibilities. The truth is they are not. So we come up with interpretations to eliminate the weirdness of the biblical worldview that makes us uncomfortable. Problem solved!

We're on safe ground to presume that self-interest and hubris are at the core of the rebellion.

God doesn't save us to perpetuate a particular Christian sub-culture. He saves us to advance a supernatural kingdom that is not of this world.

When biblical material touches on the natural world, we can legitimately use the tools of science. Sometimes that shows us - no shock here - that biblical writers didn't know as much as we now know about the natural world - but God knew that when he picked them, so that alone tells us that "doing science" that would satisfy a 21st century - and beyond - audience wasn't what God was interested in with respect to the enterprise of producing Scripture for posterity.

What I mean by context is worldview - having the ancient Israelite or first-century Jew in your head as you read. How would an ancient Israelite or first-century Jew read the Bible - what would they be thinking in terms of its meaning? The truth is that if we put one of those people into a small group Bible study and asked them what they thought about a given passage meant, their answer would be quite a bit different in many cases than anything the average Christian would think. They belonged to the world that produced the Bible, which is the context the Bible needs to be understood by.

Angels can fail because God allows them to make decisions and they are lesser beings than the perfect God. They can go astray, but the task is legitimate. God never tells they aren't allowed to instruct people - "just shut up and babysit them".