Warrior having +2 armour for 2 mana implies +1 armour is worth 0.25 mana.
Lmao, you clearly didn't read my post.
The entire point of this thread is to ask if 1 Armor is actually worth 0.25 Mana (or if Warrior's HP is actually worth 2 Mana).
All 2 mana hero powers were designed to be balanced roughly around each other. Demon Hunter came later, so using him for reference is wrong.
Also combined effects cost more. Blessing of Might + Hand of Protection = Seal of Champions easiest example. Maybe by your brain gymnastics Druid's hero power is not worth it if you add up the exact values, but because it gives both attack and defense, both offensive and defensive uses then it automatically costs more as he merges 2 effects.
Shaman is the only HP I would look to change just because it should at least be consistent and interactive with it's kit. Other than that, you're basically getting similar value in comparison with the other classes when it comes to HP's. Spending 2 to deal 2 to the face doesn't seem that great when you need priest or warrior can just counter your HP.
Honestly the only mistake was them giving Demon Hunter a one mana HP. It just doesn't sit right when the other 9 heroes all have a HP that costs 2. It just feels lazy that they couldn't come up with something more creative and just took the easy way out.
I'm sorry, but saying that the HP design was the lazy way out is just objectively wrong. The HP was infact the probably most changed part of his kit. They always wanted DH to be an attack focused class and experimented with stuff like "2 mana: Gain +1 attack, can be used twice each turn", "2 mana: deal 2 damage and to your hero", "2 mana: gain +1 attack and ignore taun" or "2 mana: Gain +1 attack, attacking generates wrath" and more. The later one was supposed to be a demonhunter exklusive resource, but they scrapped it because they didn't liked how it forced every current and future deck to include cards that use said resource aswell as some other problems.
At that point they revisted some of the previous scrapped HPs under the context of the already designed cards. That's when finally setlled on the 1 mana 1+ attack HP we know today. The fact that it was only 1 mana made the class feel fresh and sets it apart from the other 9 in a unique way, which were one of the goals when designing it. They also adapted some of the previous "wrath" cards (like Eye Beam) when they decided that outcast will be the DH main mechanic.
The Druid hero power stems from a time where accumulating even small amounts of armor could win you the game, best example being the matchup against Classic Freeze Mage. In such a scenario 1 mana for 1 point of armor, with infinite uses, is invaluable.
I agree though that today the Druid hero power is strictly inferior, and I don't know if balancing it through more powerful cards is the way. Pressing your hero power should be a *somewhat* meaningful event, or at least have some kind of exciting synergy with the class - but I can't see it in Druid at all.
Did anyone play the recent Book of Hereos with Malfurion? The Powershifting card you get is exactly what I would want for Druid, thematically. Maybe even as baseline new Hero power (nerfed, of course).
Turn Two hero power for two mana, the entire turn is used to "transform" into cat or bearform, lasts for the next two turns with an upgraded effect (use still costs two mana, granting either + attack or + armor).