I haven't posted here in a while, so I thought I'd comment on the last page of stuff.
Re: vanilla cards in constructed
Yeti in constucted is a thing. Ogre is not, because it has to compete with rare-legendary 6 drops like Cairne, Sylvanas, The Black Knight, Argent Commander, and Sunwalker. But there's no 4's with such big blowout abilities. A lot of decks don't run Yeti because they're too aggro for it, but if you're going to run 4 drop minions, they're going to be Twilight Drake, Violet Teacher, Sen'jin, Yeti, or something class-specific (Water Elemental, Arathi, Kor'kron, Keeper). Yeti can easily make the cut in midrange decks running 3+ 4 drop minions. For a while they were super-popular for Druid, since Innervate+Yeti on turn 1 is sick, but now it seems like more people are either going for Violet Teacher or Ancient Watcher (Yeti in disguise).
Re: warrior aggro in arena
I think not everyone agrees on what the term "aggro" means. Basically all decks vie for board control for a while and then at some point switch to going for the face. Some decks like the all-out aggro Hunter in constructed, the turning point is the coin toss, and for other decks it's after you run out of cards, but usually it's somewhere in-between. Warrior can have it be kind of early because (1) Fiery War Axe and Arathi Weaponsmith can get you a really strong board position early, and (2) Korkron Elite, Reaper, and Heroic are good at going for the face. Mostly I'd say you start picking a little more aggro-minded if you get multiple Reapers and Kor'kron early, since Fiery War Axe and Arathi are good for a more mid-range or control style as well.
Rogue you can start draft aggro from the jump, and is probably the best aggro class. But Warrior, Druid, Mage, and Paladin can also turn into pretty good aggro decks if your draft goes that way. (Hunter you always draft aggro too, but preferably, you just don't pick Hunter.)
Re: Mage being the best class
Mage is probably the best class in arena (Paladin is close). Mage is probably the worst class in constructed (Priest is close). How does this happen? Two reasons:
(1) Weak higher rarity cards. Seriously, there really aren't any good higher rarity Mage cards since Blizzard and Pyroblast got nerfed.
(2) Poor anti-aggro. Aggro is much faster in constructed than in arena because you can really finely tune your aggro deck. Mage doesn't have any useable AoE until turn 6. And mage doesn't have any source of heal besides Ice Barrier, which is not particularly inspiring, since it lacks the versatility to do anything other than heal your hero.
Re: Hunter hero power
It's the worst one, imo. Warrior is similar, but offers a little more versatility. It's usfeul in 2 situations: (1) when you're racing life, and (2) when you're trying to prolong the game. Hunter can only do (1). It's close though, because Hunter can use the hero power to force the game into (1).