*FON + SR combo nerfed. FoN should spawn minions that can't attack face (so it's a board control tool). This combo really limits what Druids can play as far as deck choices go.
Druid can't survive without FoN+Savage Roar as a finisher. The only archetype that remains after removing the combo is Ramp Druid, which isn't good enough right now. It's almost Shaman tier.
*Shredder nerfed from 4/3 to 3/3 (still a good value minion but this makes it less likely to trade up and do more face damage). This card limits the design space of BOTH 2 drops AND 4 drops.
I generally prefer Shredder being a 4/2 to a 3/3. That more closely mirrors Piloted Sky Golem and people don't consider that card problematic despite its similarly to Highmane. Stuff that pops should have more attack than health because you want to make these cards easy to pop. It prevents the cards from being too slow and gives you more options to deal with them.
*Mysterious Challenger nerfed. Probably make it a 6/4 to be honest so it remains in BGH range after Competitive Spirit/Avenge.
That really doesn't do enough imo. I hate the design of vomiting stuff from your deck onto the board. It should basically not exist, but if it must remain in the game, cut it down to two secrets and make it a 6/5 or 5/5 or something.
*Knife Juggler changed from 3/2 to 2/2 so it becomes less of an offensive minion.
The stats have almost nothing to do with why the card is as strong as it is. People hate playing it on curve anyway. I don't think Knife Juggler is really all that problematic. It's dirty vomit minion cards like Muster for Battle, UTH, and Implosion that are the problem. Remove those and Knife Juggler only finds its way in token and zoo decks.
*Mad Scientist should either be a 3 drop or a 1/2 minion at 2 mana. This card limits the design space for future secrets.
I used to be on the 3 mana train but something I really don't like about this card is the fact that its power level changes based on what class it is in. It is balanced in Paladin but not Hunter or Mage. If you make it 3 mana then it basically turns into a Mage-only card.
Secrets should be played from your hand. it needs to be a strategic decision so you can use secrets to bluff or use them proactively like Loatheb to block your opponent's next move. That's way more fun than just having secrets pulled from your deck while you give two shits about what it ends up doing because whatever it does is basically okay value. Make it a 2/2 that just draws a secret from your deck. Then it becomes a situational cantrip that encourages a secret strategy without forcing it. And then its power would be the same in every class. And then you might actually run more than 2 or 3 secrets in that kind of deck.
*They need to do something about Void Caller eventually because that card 100% limits the design space for future demons. Getting a 9/7 as a deathrattle from Void Caller is extreme.
Lets be honest. If Blizzard is okay with voidcaller pulling out Mal'Ganis now then you can't say it limits future design space. And while I have always said that voidcaller is possibly overpowered its impact wouldn't be nearly as bad if we went back to a meta where people ran BGH again.
*Implosion RNG needs to be looked at because it's a joke.
Crackle and Implosion should just be straight up removed from the game. The worst kind of RNG.
*Last but not least... Dr Balanced should really just be a 8 mana minion just so that aggressive decks have to think twice about running it.
The game doesn't need more 8 mana minions. It needs to remain in the 7 slot. Make the main body a 7/5. Suddenly it doesn't stack so well in minion trading and it gets punished by Sylvanas. It would be about on par with Baron Geddon which is perfectly fine for a 7 drop.