I'm really not sure what they can do with Warriors that won't break PvE traditions WHILST actually fixing PvP. The games are just so, so different.
For starters, we need to consider what Blizzard will do with regard to Ability bloat across the board. My best guess is that the passives that we pick up from L3-90 will be removed for the most part in in favour of an active and expansive talent system. Do you know what works WELL with the new talent system? For the most part, people pick what they want. None of that 3/3 or 5/5 crap that you HAD to take (in some cases whether you liked it or not!) But, we're landed with so much stuff! In order to reduce ability bloat, in 6.0, I think our talent tree will consist of the MAJORITY of our skills. You'll actually have to elect to pick Cleave, and Banners, and Thunder Clap, with only a few key skills (Disarm, maybe... and Charge, Battle Shout) being mandatory.
What does this solve? Well, ability bloat for a start, because (again, hypothetically) you'll only be able to choose 60% of the talents on offer. That means you'll have no more than 18 abilities (as an example) and also a limited number of passives. Are you a Fury warrior who only really like Single Target stuff? Forget Cleave, then, and Thunder Clap, and Whirlwind. In exchange, you can have Throwdown, Rend, and Warrior Vendetta. Of course, this would need some balancing - but what I forsee is an increase in the NUMBER of talent rows (although the layout might be different - like the old 'trees') and far fewer baseline abilities. I expect to have to chose between three types of stun, AoE skill, charge, banner (to wear), raid cooldown, shield skill, armour buff, ranged ability, etc. But not just that, the system would actually incorporate lots of our standard 'you get this at level X' into the trees so we 'pick' more of the skills we end up with. My 18 level 90 active abilities might be 64% similar to yours; I have Cleave, Whirlwind and Demo Shout - you have Throwdown, Improved Hamstring, and Zerker Stance.
Regarding Stances, I still think they should do what I thought they should do 2 years ago, and that is to have Zerker Stance as a (Blade Flurry) AoE stance. Make the Stance 'modify' 5-6 abilities to hit multiple (3-6?) opponents. Heroic Strike would become Cleave; i.e. Throwdown would become Shockwave; Mortal Strike would become Mortal Slash; RB, Devastate, Slam, Wild Strike, etc would all 'meatcleaver' for 100% of their damage or something. Essentially Blade Flurry for Warriors. It would make AoE dynamic, it would make stance dancing FUN, and it would mean that we wouldn't need a completely, separate (and awkward) rotation for AoE (hello Fury).
Disarm is solid, and should have a bearing on casters to the same level that Silence affects us.
Piercing Howl SHOULD be baseline, I agree.
Rend should replace Hamstring and provide the Bloodbath effect which would be REFRESHED by MS, BT and Shield Slam. Remove Deep Wounds - it's lazy.
Shield Use might get a new UI, but for the TWO abilities that we have, I think we need to just get rid of shields for DPS warriors and give them abilities that don't require them. Angle the hilt of your weapon to reflect the next spell, etc.
Charge needs a 2-sec 70% sprint at the end to catch up to moving target. The current stun isn't good enough. Either that or the Warbringer effect (5.4) needs to be baseline.
Heroic Leap needs more leeway... we really can't afford not to jump up 4% inclines in Twin Peaks. It's getting silly. It's a 'cool' ability, but it really, really, really, isn't working to the consistency it needs to in PvP. Flat arenas MIGHT be okay, but for World PVP, RBGs, and BGs, it's simply too poorly done.
CHARGE... needs to generate 100 rage. Very sick of getting into a PVP fight, spending the rage I have on Thunderclap/Hamstring and not being able to do much else. "CS or MS, then - they're rage-free" is a valid argument EXCEPT that our PvE rotation on Arena and PvP in general is PREDICTABLE. With their 100 energy a rogue can do one of many things.. we are much more limited in that regard. Generating full rage with charge would allow us to burst during our pitiful uptime on ranged classes (currently) and would also limit more "not enough rage" problems during clutch defensive situations.
Have Energy as a main resource. And RAGE as a secondary. I know you won't like this, but hear me out:
Having Energy refresh at a certain speed will do LITTLE TO NOTHING to the amount of times you can hit Bloodthirst, Shield Slam, MS, etc, etc because it will be TUNED to let you generate the same amount of rage! Having energy as a main resource (instead of time/cooldowns) will simply mean that is we NEEEEED that Thunderclap because the Rogue is going Swifty, then we can hit it. As it stands, Rage generation when separated from a target (i.e. a Mage or Hunter) is almost non-existent. Being able to get to that target and having the Energy to Disarm, Stun, Thunderclap or whatever else costs rage, would be a huge quality of life improvement. We're the only class with an archaic and poorly balanced resource. I don't want a secondary resource because it's 'cool' I want one because using Energy for some more clutch stuff will mean we can have Rage for FUN stuff, like Raging Blow, Slam, etc. There have been too many times when I haven't had enough rage for a clutch Thunderclap, or Shattering Throw for me not to think this is a good idea. Important Stuff: ENERGY... Bonus Stuff: RAGE! I know it's a bit 'Rogueish' but it would also alleviate this buff-nerf cycles we've been stuck in since vanilla! it would also make Haste more attractive.
More than anything I want to be able to stick to my target more. I want to be updated to be able to deal with Post Haste, Readiness, 25sec Deep Freezes, Emancipate, Freedom, Deaths Advance, Necrotic Strike on my Second Wind, etc. Get rid of Throw and Heroic Throw. Stormbolt Baseline makes SOOO much sense. Give us some kind of stickability.