Title says it all. Well, in case you haven't heard of, a developer called Matt London wrote a post on Twitter, indicating that Blizzard is planning to bring the best experience for Wild format.

I wonder what's going to happen but unless they look into these issues below, I'm not holding my breath. These are my takes and I would like to hear your thoughts as well:

General

• The cost of cards shouldn't be reduced below 1 Mana, no matter what. Mana cheat went way overboard that a hard rule must be applied. That means cards like Emperor Thaurissan and Insight can reduce the cost down to 1 Mana, similar to how Arcane Luminary functions. This rule will keep Pillager Rogues and Secret Mages to not spam 0-Cost cards.
• If necessary, a card should have alternative/different variant for Wild format. For example, Contract Conjurer might be OK in Standard but not so much for Wild.
• A graveyard system must be implemented so Big Priests can't resurrect same minion over and over again. Right now, if Blood of G'huun dies once, you can play 2xResurrect cards right away. Here, I propose you can play Resurrect only once if G'Huun died once. This rule will also affect N'Zoth cards and similar ones, to a degree.

Druid

• Play Floop's Glorious Gloop to gain infinite mana, if utilized well. How about a hard cap, which you can gain up to 10 Mana Crystals, even if you have Guff Hero card played? Like, you have gained 9 Mana and spent them, then 2 minions killed but only one is granted to you, not two. It also shouldn't stack with cards such as Solar Eclipse.
• Wildheart Guff should have 15 Mana Crystals at max, not 20.

Mage

• Kirin Tor Mage cries in the corner because Kabal Lackey and Anonymous Informant are much better. These cards should reduce the cost of secret to 1 Mana, not zero. While at it, their cost should be upped by 1 Mana.
• Kabal Crystal Runner should reduce her cost by 1, not 2.
• Contract Conjurer should cost 1 less for each secret controlled. Maybe make him 7 Mana, perhaps?

Priest

• New graveyard system, please look above.
• Some resurrect cards Big Priests use should have mana cost raised by one. Candidates are; Resurrect+Eternal Servitude.
• Shadow Essence should summon 3/3 or 4/4 minion, not 5/5.
• Illuminate should cost 1 Mana and reduce the cost of spell by 2, not 3.
• Radiant Elemental limits design for future Priest cards, which has proven pretty much with Mind Sear. This card belongs to Ungoro expansion and it's Elemental. Thus, I propose the following change: "Your Elementals have +1 Health" which looks thematically fitting.

Rogue

• Maybe not a problem right now but either increase the condition for The Caverns Below or change its reward to set minions to 3/3 instead of 5/5.
• Swordfish should either have 2 durability or grant +1 Attack.
• Cutlass Courier has very good stats for his ability if compared with similar cards. Reducing his stats to 1/4 looks like a right balance choice.
• Scabbs Cutterbutter should be...
  • 5 Mana, rest is same.
  • 4 Mana, reduction is 2.
  • 3 Mana, reduction is 1.

Shaman

• Splitting Axe converted into a Deathrattle card rather than Battlecry one prevents the insta-snowball effect.
• Totemic Might and Totemic Surge should cost 1 Mana.
• Why are Thing from Below and Gigantotem same cards? To differentiate, I suggest Thing from Below reading "Cost 1 less for each Totem you control." 

That's all what I can think of. Let me hear your thoughts. With the insight shared from Blizzard, I really look forward to see Wild format grow even better.