If an aggro deck lets you get to the point where you can play Alex you've either already gotten very good draws or they're doing it wrong lol
And I agree that it's definitely the best way to finish, basically hijacking them before they expect it, but I dislike how effective and important "burst" is instead of more sustained back and forth.
I agree, and I think Blizzard does too. They have taken many measures in the past to remove or at least weaken various one turn kill combos. Warrior used to have numerous OTK combos before the change to Warsong Commander. The increase in the mana cost of Leeroy Jenkins made it useless in most decks (Miracle Rogue and Handlock specifically) - and by useless I simply mean less effective than other means of burst finishers that are still not as powerful as the Leeroy combo finisher used to be.
Overall I feel like the game is a lot less dependent on burst damage from the hand than it used to be. This is a good thing, since there is no strategy in constantly having to play around 20+ damage that your opponent may or may not have sitting in his hand on any given turn. On the other hand, there is so much removal in this game that its nearly impossible to set up any kind of 2-3 turn combos. You can literally never be even slightly confident that a minion you play on your turn will be alive the next turn, even if you play it into an empty board (stealth minions are a minor exception, but even they are susceptible to AOE's and various types of non-targeted damage).
And so we end up with the current meta, which is comprised largely of minion based aggro decks. I think the problem is that there aren't enough ways to punish ultra-aggressive decks. The only viable option essentially is to outlast their initial barrage and wait for them to run out of cards. For zoolock that can be nearly impossible since their hero power lets them draw two cards every turn - after 4-5 turns of that, they've drawn more extra cards than most other decks ever draw in an entire match. For face-hunter you have to not only outlast their initial rush, but you need to do so with a good 20 hp left otherwise they will simply whittle you down over the next few turns with hero powers, weapons, kill commands, and charge minions. Same thing basically against mech mage, as they have arcane intellects to help draw through their deck, so as long as they do 10-15 damage with their initial rush of minions they can easily finish you off with their ridiculous amount of face damage spells. In all cases you are usually lucky to even survive their initial rush, any non-aggro deck generally has a lot of cards that are completely useless until late game, and if you end up drawing even a few of them early in the game you are basically dead in the water.
I don't pretend to know the solution to this. There is already tons of AOE in the game (too much, some might say), so I don't think the answer is to add more and cheaper AOE options. I think taunt minions need an improvement across the board. Right now most minions with taunt are simply not effective enough for their mana cost. Target Dummy, Goldshire Footman, Shieldbearer, and Frostwolf Grunt are all jokes, leaving Annoy-o-tron as the only reasonably useful taunt for 2 or less mana. In the 3 mana range there is almost nothing worth putting in your average deck - deathlord is good against aggro but far too dangerous to ever play against a mid-range or control deck, lil'exorcist also pretty good vs aggro (since they tend to run a lot of deathrattles) but next to worthless against anything else, and every other 3 mana taunt simply has far too weak stats to be worth using. The first 'good' taunt minion comes at 4 mana with Senjin Sheildmaster (and Arcane Nullifier - but only for heavily mech based decks), then Sludge Belcher at 5 mana, and then finally Sunwalker at 6 mana. Outside of a few class specific cards (druid of the claw, king of beasts), this is pretty much all there is in the realm of not-terrible taunt minions. It's just not enough, and most of the time your taunts simply get taken out by a cheap removal spell or simply end up doing a 1-for-1 trade with one of the opponents cheaper minions.