What I'm enjoying the most with the Reno Warlock deck, and I'm guessing from all Reno decks is that your games are pretty different each time. When you play a regular deck, it's generally very focused, and it has specific win conditions, and the gameplay varies little from game to game. You have specific answers to the problems you face, or have trouble dealing with some of them, and the games end up being somewhat routine.
Having 30 different cards changes that fundamentally in that your deck is less focused, and each game play differently because the likelihood of getting the same hand each game is reduced. Also having 30 different cards, you have a lot of different ways to deal with different problems presented to you.
I find the deck to be more fun to play because of that, each game is a bit more different than usual, and your win condition is not always the same. The game feel to me to be a lot less routine and therefore more fun and exciting each time.
I know it's too early to know how big of an impact it will have on the meta and the game in general, but it would be interesting to see more cards like these in the future. Cards that do something different if you have no duplicate in your deck. They don't necessary have to be has game changing as Reno, but it could influence deck building to some extent.
Anyways, enjoying the game quite a bit right now.