Snow White and the Huntsman/WMG

Christianity and paganism featured in the conflict between Snow White and Ravenna.
The first time we see Snow White as a young woman, she's made a cross and is reciting the Lord's Prayer. When Snow White is lying in state, the Huntsman says that she's now a queen in Heaven; the Virgin Mary is often referred to as the Queen of Heaven, and this may refer to Snow White becoming a saint. When she rises from the dead (sadly, not after three days), she's clad in flowing white, symbolizing her rebirth. Contrast this to Ravenna's bird motif and shapeshifting, common in pagan thought; Finn's reference to "the otherworld" rather than Heaven, Hell, or Purgatory when fighting the Huntsman; and the last battle, when Ravenna stands in the middle of the fire, presenting a Devilish appearance as the flames surround her.

Given what we see of Ravenna and Finn's village, and that their mother knew what looks like a kind of folk magic, it's possible that pagan beliefs were predominant in their era of birth. Later, Christianity has spread, becoming the dominant religion in "civilized" areas and making them, specifically Ravenna, even more outcast as time goes by.

The "Mirror Man" is the manifestation of the first man who 'ruined' Ravenna.
It's implied that the mirror is nothing but polished metal: While watching Ravenna converse with it, all Finn sees is his sister addressing thin air. The specter we see emerge from it is just a facet of Ravenna's madness, representing the first man who ever used her: Giving the Mirror his likeness, probably subconsciously, is an act of revenge, as it has no choice but to praise her as "the fairest in the land." However, her psychological scarring is why the Mirror's tone is less sincere and more neutral, even sardonic; Ravenna's reaction to hearing that Snow White will surpass her is partially a response to the news itself, and partially in response to having the man she loathes, who sparked her hatred of all men, once more getting ready to pass her over her in favor of someone younger and prettier.
 * If the Mirror Man is just part of Ravenna's madness, then it wouldn't be able to help her find the women who are a threat to rivaling her beauty and it wouldn't be able to give her the tip about Snow White being the one who could either destroy or save her.
 * The mirror itself is still magic, like a crystal ball, but the metallic figure is purely a figment of Ravenna's mind.

The Huntsman was trained to fight by the dwarves.
Note that The Huntsman uses an axe primarily, with smaller axes as secondary weapons. This is despite his name implying that he would be better suited for hunting weapons. Even the standard issue sword that soldiers would be given (he mentioned going to fight in the war before meeting his wife), would make more sense, as we see no other human characters using axes. Then notice that the dwarves all favor axes and pickaxes for weaponry. That, with Beith's comments about already knowing The Huntsman from previous experiences, hint that they trained him to fight, with their weaponry and fighting style.
 * In fairness, the axe is a traditional tool/weapon hybrid, since "huntsman" and "woodsman" are often synonyms; an axe is useful for splitting wood and removing obstacles as well as for defending yourself while in the woods, usually against wild animals, without having to carry a separate tool and a separate weapon. In Little Red Riding Hood, the titular girl is saved by a Huntsman wielding an axe, who is sometimes known as the Woodsman. Hunters didn't just use bows and arrows, and there are modern hunting axes today, though they're not meant for battle. Of course, it's likely that the dwarves did teach this particular Huntsman to fight, but his choice in weapon isn't necessarily an indicator.