Succubus: In the same vein as the imp avoids harm, the succubus is known for slipping in and out of sight on the battlefields, attacking when least expected, and relishing in the pain delivered to their opponents. In the same vein, both pain and pleasure enact a power to the succubus. To the demon hunter bound to a succubus, this might showcase itself with a particular knack for invisibility spells, turning pain into power, and even an affinity with the use of charm spells.
One of my favorite features is the Smart Injection System, which automatically determines the optimal place for your character to get started with the guides, based on your level and quest history. In other words, it doesn’t matter what level you are currently, you can jump right in and continue seamlessly with the guides. It also means that you don’t have to be a slave to the guides, they work perfectly even if you’re also leveling in instances, battlegrounds, using heirlooms or rested EXP. If your level ever gets ahead of the guide, just use the built-in feature to skip to the right place again. Very cool.
2. Your DH needs supplies on a regular basis. They can only carry so much food, clean drink, medical potions and whatever else they want/need at a time. It's pretty realistic that they would need to visit a market every so often, and large faction markets will have the most variety and types of items to choose from. (My DH has been a recluse in the wild for some time, and she is stinky, dirty and has eaten some questionable stuff. This isn't really ideal and a Dalaran doughnut would be pretty flippin nice.)