House of Wolves brings many changes to Destiny, one of the most beneficial being the new upgrade system. Rather than having to re-level all previous weapons and armor, all that is needed is etheric light, which is much easier to gain. In addition, House of Wolves brings Trials of Osiris which will give much needed attention to Destiny's competitive multiplayer, further augmenting its replayability.
There is amazing new armor for the Hunter, Warlock and Titan classes, and three new Crucible maps. While the narrative problems won't be fixed, there is a ton more quality content based on fan feedback, which is most important. They also replaced the Raid with an entirely new type of event, and even rolled in end-game PvP.
Destiny encountered a string of consumer complaints after several glitches and bugs were discovered in the game. House of Wolves now has Destiny making fixes and patches that are supposed to remedy the mistakes of the past, yet if history is any indicator it does not appear that these fixes and patches will fix these issues.
House of Wolves is going to do the same thing as what happened to Destiny. The previous DLC got the same thing wrong for Destiny, and it will be no different in House of Wolves. The game, which is also known as the second major piece of the Destiny series, will be nearly the exact same thing, involving this mistake.