I'm scared to go off on a rant, but basically, button bloating and the wrong approach to things ruined the game, and stubborness in not pruning unnecessary stuff added later to an otherwise solid and working wireframe.
I liked Wrath, but they don't have to copy Wrath to make the game good again.
What they need to do is realize what made the game good in the first place in Vanilla, TBC and Wrath and why it all went downhill after.
Let's say that Wrath per se is the ideal state in which this game should be in terms of class design, minus some tweaks. In this example we will mainly have Warriors as focus because that's the class I experience the game firsthand and, like it or not, is a good class to judge the metagame with being the simplest melee by design.
Cata launches, a bunch of buttons gets added to the spec + some questionable talents make some abilities inherently broken.
So now Warriors have Heroic Strike hitting like a truck due to Incite autocrits, and take everything in 20 yarde out of stealth due to a talent in Arms' row which you basically take because it makes Pummel cost no Rage.
Heroic Leap's introduction takes Intercept out, because the new tool has to be the choice and not the old one.
The buttons are basically bloats. Slam gets empowered by Lambs to the Slaughter, a three MS cast which means at least fifteen seconds of continuous uptime, which is unsustainable at best in a meta where almost every melee sports a 1s gcd.
And Warriors gets stuck with MS, Rend, Execute, Overpower, Slam, Heroic Strike and Colossus Smash. Five buttons that do damage, one that does damage and burns excessive Rage and one that does damage and makes the damaging buttons do more damage.
Emphasys on five buttons that do the exact same thing, on paper.
Because Overpower has always been the saving grace of Warriors against melees and its synergy with Rend opened up for great controlled burst in expert hands, and MS is our distinctive attack and debuff.
Execute is worthless in this scenario, so come MoP more buttons bloat the sun but Rend gets removed.
Execute stays worthless and Heroic Strike ascends to broken status, then gets back to nigh anonimity. Slam, obscene mobility and senseless self healing are nonetheless able to carry the class to god status.
Enter WoD, exits 70% of our toolkit.
Did you watch the regionals in which Joefernandes sat in CCs for two minutes and some against an RMD, with the Mage and the Rogue having a minute adding both the CCs they've been targeted with.
The Mage, the Rogue and Joe, all of them, had an output of approx. 4mil damage each.
This means that the two buttons we're left with have issues. That's the conundrum: you don't touch what's not broken.
Current talent system is a great addition for further abilities on a solid class design, even if the talents themselves leave a lot to be desired.
As for the current state of the Warrior, a simple two buttons addition would make a lot for the feel of the class: Heroic Strike and Deadly Calm.
And fucking Charge stun. Holy shit.