Hope you're ready to open your wallets, blizz just announced they are going full P2W with next rotation. Several standard cards being banned to wild and no adventure relase for the year.
Well... On one hand, it will be a little more expensive per year. I make pretty much every meta deck with about 120 packs per expansion. If you play to complete every daily and get a few 10g for 3 wins and such, you end up with around 500g a week or about 110 packs per expansion and paying for the adventure with gold under their previous model. This drops to about 86 packs per expansion with the new model. They have promised additional gold logging in daily, so we have to wait and see how much it offsets... It would have to be around 20g per day to bring things back to parity with the previous model. I'm willing to bet money it'll be within ±5g of that so the end result is very similar to their previous strategy for a F2P player. The math is simple, and the entire game is basically a math problem... they know their players will do the math and will whine to high heaven if it's too unfavorable.
On the other hand, adventures were not all that impactful for changing the way the game is played and Hearthstone's largest problem is that a meta gets stale and the game kinda drags. Karazhan, for example, changed things very little. The most fun in hearthstone is the week or two following an expansion release. People are playing tons of different experimental decks and it's just when the game is most fun. A change like this is very likely a positive experience for a dedicated player.
For me personally, I welcome it. The money aspect has little to no effect on me. I play regularly and have since Naxx. I get rank 5 each month for the dust value of the golden epic (6k dust per year). I play tavern brawl to get a pack a week (another ~5k dust per year on avereage). I do dailies and sit on gold waiting for an expac. I buy the $50 intro bundle each expac and supplement those packs with gold for around 120 packs total. I don't expect this to change. With this I have always been able to get all the commons and rares, then craft the epics and legendaries I'm missing to make whatever meta decks I want to play. Doing this, I stay caught up and am currently sitting on over 10k gold and 10k dust right now just waiting for the next expac. Is this P2W? Maybe, but I don't really consider it that. It's like ~$10/mo to play a living game. Cheaper than when I played WoW, but more expensive than when I bought XCOM:Enemy Unknown bought a year after release and spent 500+ hours playing it.
The problem with Hearthstone right now is that the game isn't "living" enough. It doesn't change often enough and adventures don't change it enough when they happen (Karazhan example again). This should be a step in the right direction for keeping the game more interesting in the long term.
As for the cards rotating out of standard, you say it like it's a surprise. Several standard cards being banned to wild... umm that's a rotation. Several hundred cards get banned from standard and move to wild... not sure what you were expecting to happen.