Classic is basically dead: based on numbers from hsreplay.net, the top5 most popular decks (last 7 days, diamond to legend) were played 182,000 times. The corresponding number for Classic is 6,050, that is, roughly 30 times less (I implicitly assume that the fraction of deck tracker users is similar across game modes).
One way to fix this would be to simply restart the cycle of set rotations!! Every month/season, a new expansion/adventure/mini set would be "released". So basically each month we could play a "new" standard meta from the past!! This would be beneficial for both players and Blizzard:
Lots of fun with old decks!
The meta never becomes stale as it changes every month
Increased value of the card collection
Little maintenance required (they already figured out the "right" balance patches and know how to release "new" sets)
Newer players would buy more wild card packs/bundles!
Once the cycle reaches the current standard expansions, it would simply restart (that is, the most recent expansions are exclusive to standard).
Only Blizzard is greedy enough, and the blizzard community dumb enough, to actually want something like this.
Classic HS/WoW is the f*ing dumbest idea in the world and you can't make it amazing cause it's a dumb idea to begin with and should have failed way harder than it did, if it wasn't for the dumbest community in the world.
I'm already laughing 10 years from now when braindead people ask the "Very Classic" version of classic HS/WoW after it catches up with the live game.
If u make rotations so often with other expansions, u force people to go back to Standard. What about those who don't own that many Standard cards and have almost 0 wild cards?
Let Classic be Classic, since most of the players, like myself, already invested lots of dust to craft Classic Decks. If you just rotate them with something else, u have here a Standard 2.0, and most of us with not so many cards would have to suffer and we'll be forced to spend real money on past cards.
Although, yet I have a different opinion, maybe we all can agree that a 4th game format, like you stated in ur argument, may be the answer.