Pokemon White 2 adds a lot of new elements to the Pokemon scene, and with each addition Pokemon just gets better.
As for the new additions, there are plenty of them. Perhaps, the best addition so far is the new medal system that works as a kinda achievement system for Black and White 2. Like looking at trash? Here's a medal! Like spending a lot of money on items, here's a medal! You took on the elite four with one pokemon? Medal for you! The simple amount of joy that can be gained from these medals makes me wonder why Nintendo just doesn't cave in and just make an achievement system of their own. Nonetheless, medals are simply the tip of the iceberg because what really separates B/W 2 from its former "special edition"-ers is a new story taking place over 2 years ago. It's quite nice to see such a familiar place change in such a short time of two years. A lot of new areas are accessed, and the majority of the locations feel new if they weren't already. The new story also helps makes things fresh because it feels like you are playing the Unova regions in the eyes of someone going on their own journey for the very first time. Although as stories go I have to say that B/W 2 isn't as great as Black& White's story. It's just not as eye catching or complying compared with the first. The fact that Black and White made you have about 3 different rivals all fighting now and again made things really surprising and encaging. B/W 2 story just feels a bit more generic compared to the first, and really the only thing that really makes it interesting is seeing the older characters interact with each other again.
I also liked that BW2 gave me the ability to change difficulties, but why do I have to beat the games in order to even pick them? And why does White 2 and Black 2 get easy and challenge mode separately that you actually need both games or someone who as the game opposite of yours to give you the key? This seems far more counter productive than anything else, and really makes me wish I could just start a game on challenge mode without having to beat the game already. Other additions like grottos and the shopping center you own are great additions too. You can get people you trade with to open up shops and you get to upgrade them so you can make your life easier in the Pokémon world. While the grottos provide to be a neat little addition that lets people get hidden ability Pokémon without the need to go to dream world. The final addition I like to talk about is PWT, or Pokémon World Tournament. PWT is, in all aspects, a dream of Pokémon fans throughout the ages and one that really sets white/black 2 apart from any other previous game before it. Being able to battle older gen gym leaders and champions just gives this game so much nostalgia points that even older fans couldn't hate it. They even added a bunch of new remixes for the gym leaders and champions that returned.
Pokemon Black and White 2 really does show that Game Freak can just keeping adding on to Pokemon games, but still hold the same tired and true method of catching them all. While the story isn't up to par with the 1st Black and White, the fact that they add more things than I can list on the top of my head says that they really did work hard to provide a new experience with the Unova region. And with that note, objectively, Pokémon has never been better.