2-for-1s aren't necissarily bad as long as they are strong enough, but the problem with warriors is that they have absolute terrible draw (complete dependence on battle rage) in addition to all the 2-for-1s. That combo is just bad design.
2-for-1s are frowned upon in most competitive TCGs. A large reason people don't play aura cards in Magic the Gathering (Outside of a few decks) is the fear of your creature being murdered the second you go to attach an aura.
The same goes for anything trying to remove stuff. If you're going to use two cards to deal with one thing (It doesn't matter how powerful the two cards interact) you've already set yourself down, and have one less card than your opponent does.
The warrior weapons are pretty solid forms of getting the most bang for your buck, but even they come with a drawback (Having to hurt yourself to kill creatures). Meanwhile Gladiator's Long Bow for Hunters, is probably the best weapon in the game. They get all the perks of the weapon with no downsides.
If a warrior could Whirlwind, and than have execute kill multiple wounded minons, than it would be Ok, because the card combo is killing multiple things at once. As opposed to just one assured kill.
I mean look at Mortal Strike. Really? No one in their right mind is going to play that card, because there other cards from other decks, that just flat out-class the Warrior's cards. IE Fireball.
I really like the design and flavor of a lot of cards from the warrior, but they need to be much more potent, if the Warrior class is going to be taken seriously. I mean come on Starsurge is 5 damage AND draw a card. A kill spell that cantrips, is CRAZY. The best thing we have compared to that is Mortal Strike, and I already explained why that card is awful.