This is a big one. In the first six chapters of Daniel—the main story part—every chapter demonstrates someone doing something courageous: Daniel refuses to eat food that doesn't jive with his religious standards, he saves the wise men (and himself) by telling and interpreting Nebuchadnezzar's statue dream, he tells Belshazzar it's "Game Over," and refuses to stop praying to God, getting tossed into the lions' den. And Shadrach, Meshach, and Abednego also demonstrate courage by refusing to bow down to Nebuchadnezzar's idol and facing the fiery furnace.
All of these instances of courage have something in common. They're not based on prowess on the battlefield, or the kind of courage that kings and warriors typically deal in. They're examples of having the courage to tell the truth in a situation where the truth is unwelcome—and not only to tell the truth, but to live the truth, as well.
Lions? Plenty of 'em. The Book of Daniel certainly has plenty of dreams, too—but they're actual dreams, weird things Nebuchadnezzar sees in his sleep. Yet, like Uncle Sigmund Freud always says, "Every dream is a wish." All of these dreams—the statue destroyed by the rock, the tree that gets cut down—are wishes that the Hebrews had for the future. They wish to see the world of wicked empires replaced by a Messianic age of peace (the rock that covers the world, in the statue dream) and to see kings like Nebuchadnezzar brought low and re-educated into the ways of God.
Daniel's visions too, outline hopes and dreams for the future. They predict the end of the reign of un-righteous kings like Antiochus IV Epiphanes and the beginning of a New World. They imagine the wise and holy people who are now persecuted, raised up and ascending to a place of glory after death.
The Book of Daniel has a lot to say about power. Its message is usually "Not so fast—it belongs to God." Every king we encounter—from Nebuchadnezzar to Antiochus IV Epiphanes (the "little horn")—ultimately is humbled in some way, whether by realizing God is above all or by being totally destroyed (yep, those are the two alternatives pretty much). Daniel keeps demonstrating that all power and glory belong to God and shows that God will give that power—and take it away—from kings and conquerors when he pleases. The examples given in the quotes are mainly examples of power getting taken away from someone—showing how all power ultimately needs to go back to God.
Come on, you knew that with so many lions running around this had to be theme, right? What's that? It's pride as in the emotion? Yeah… we knew that. It still works well here; pride is a theme that is closely tied into the power theme. Because what do kings take pride in? Their power. But ultimately, Daniel seems to be saying that, if you take pride in your power, you're going to lose it. Yet, if you're humble—like Daniel and Shadrach—and give everything up to a higher power, you're ultimately going to get promoted and can survive any catastrophe. You'll keep moving along. But pride sets up the various kings who have it for a nasty fall: "Pride comes before the fall," as the old saying goes.
No, we're not talking Ed Rooney from Ferris Bueller's Day Off here. (That's spelled principal, gang.) This theme is actually really closely related to the courage theme. Just like the kings' pride is over their power, Daniel and his friends' courage is over their principles. Those principles are related to their trust in God and their identity as a people. They refuse to compromise themselves in any way, not praying to foreign gods or eating non-kosher foods (hold the Babylonian lobster bisque, thanks). Those principles ultimately prove to be a greater source of comfort than "doing as the Romans do" or, in this case, doing as the Babylonians, Medes, Persians, and Greeks do.