Ok. This is a fun product.
For a buck (or more) you get new class options for all the core D&D 5 classes.
Here are my favorites.
Barbarian: Dancing Lights - The power of the Aurora Borealis is at your finger-tips. The is a seriously cool concept and one that should be ported over to other settings/games like Astonishing Swordsmen & Sorcerers of Hyperborea.
Bard: College of Caroling - with a bit of a tweak you can get a Mummers Dance out of this, and that would be a lot of fun.
Cleric: Domain of Cheer - Love this concept!
Druid: Circle of the Evergreen - I like this one too, not what I thought it would have been, but still really cool. Remove it from it's Christmas origins and now you have Eco-Protective Druids. Think Swamp-Thing with spells.
Monk: Way of the Sugar-plum Fairy is far more awesome than a PWYW product should have. A monk tradition. Based on the Fae? Ah..yeah! Sign me the heck up!
Paladin: Oath of Winter - "Winter is Coming". That's all you need to say. Gotta get a blank sheet and get my Ned Stark on.
Rogue: Chimney Lurk - major props for the name alone. This one is really cool too.
Sorcerer: Frozen Soul - If you get the desire to sing "Let it Go" while playing this character no one will laugh at you. They can't because you froze them in a block of ice! Maybe one of my most favorite ones here.
The Wizard, Warlock and Fighter options are also fun, but I liked these all the best.
It's Christmas, pay more than a buck for this.