Skellige is the most well-designed deck [Gwent][Opinion]
I must say I LOVE the skellige deck, feels very fresh, a very unique way to play, and still incredibly strong.
They finally managed to make a fun and strong deck that doesn't rely on drawing a billion cards, which means you can actually plan a ton turn 1 (of course you will change things based on what the opponent does), and the revive mechanic + branns clear graveyard ability makes for some incredible decisions and combos(especially when playing against Skellige). I think playing Skellige has required the most thought and strategy out of all the decks to me, and unlike the other factions I have rarely felt I lost due to luck, but due to mistakes I made.
I think a lot of it comes down to the faction ability with the respawns, along with a good amount of different unique musters. It enables so many good strategies, but all of them require great planning - baiting out scorches, setting up to have a certain set of cards in the graveyard etc. Also Cerys is the most broken cards in the game :D
Lastly it just seem you can make wonders happen with any hand, as long as you can make each of them count.
I just wish there was more! (Also monsters feel even worse now, since skellige basically does all monsters ever did except much better)
EDIT: Reason I made this is I've been seeing some hate for this deck and I don't get it, it seems really damn strong to me (maybe not auto-win like a well-built NR/NG but certainly good enough to reliably beat anything the game throws at you), and more importantly it is incredibly FUN and DEEP, and while I almost never missplay NR/NG in any big ways since the plays are so easy, with Skellige I find myself coming up with better plays I could have done to win all the time. Of course everyone has a right to their own opinion - I just wanted to add mine to the mix :D