Personally I don't see any problem with these new RNG oriented cards. Like @
4RM3D said, players who opt to use cards that are not competitive or that doesn't fit a well constructed deck archetype won't be winning many games. You'll probably see a lot of random and weird decks on lower ranks of the ladder, but as you climb up you'll stop facing them, because players at higher ranks won't play silly decks and risk losing their work. It isn't needed to banish such cards from ranked, because this will happen naturally. Of course that some of these silly RNG cards may rise to a competitive level if not balanced correctly, and in that case, I trust CDPR to fix the issue as soon as possible.
Overall, adding these new layer of RNG, as long as it doesn't affect the win ratio of the competitive and e-sports scene, is totally fine and healthy to the game. Specially with the new game mode on the verge of happening (draft mode?). Some players like to have fun with random decks and doesn't want the stress of competing on the ladder, so the new cards + the new game mode will bring much more people to Gwent and increase its player base considerably.
I'm more concerned about what they're gonna do with the rows and all the row limit stuff...