Magdks in particular do need sustain help, but lowering wings costs wouldn't do anything but increase wing spam and have forums explode about wings countering builds again (the reason why force pulse is no longer reflectable), while not fixing the actual problem. The issue is magdks are the only mag class in the game without an active source of resource recovery that is sporadic rather than continuously reliable. (magblades have syphoning, templars have rune, 5% cost reduction, 5% larger pool and 10% recovery, and wardens have betty netch, as well as resource return). Dk's recovery passive only returns stam so, while that helps block dks and stamdks it's much less useful for a typical pvp magdk, and their ONLY other recovery passive requires an ult and was noticeably nerfed in recent patches. Hardened armor being reworked to apply magicka steal rather than a weak shield for 5% of your health would be a better change and help in both 1v1 and group situations, while still making sure a skill as strong as wings in certain situations still has to be used with some semblance of thought.
While I agree with what you said, I'd rather not have hardened armor taken away from my 1vx stamDK. Hardened+vigor+igneous is pretty much the only way to survive. Unless volatile armor is changed to deal poison damage (adding damage so I can compensate for survivability else where), I don't think it's fair that the defensive Major buffs skill only benefit magDKs. Every little bit helps in a 1vx, even a 1k damage shield.
Just change Elder Dragon into a magicka+health constitution passive instead.
They both last 6 seconds, Wings reflects 4 not 3. How the hell did you come up with Wings not lasting as long yes Major Herisom is good, so is 35% extra damage. Shimmering has a Damage cap (scaled with Battle Spirt or not) Wings has no Fing Damage cap at all Sure Ice Aura is great, so is Iron Skin. No they aren’t the same, yes they are damn close to equal footing
This doesn't change the fact that wings does not do enough for its cost. Personally, I do see wings in PvP a lot more than I used to but when I talk to players it's more because there's nothing else for them to bar. Wings, a class iconic skill, should be slotted for a better reason than just to fill space.
That said, while I do advocate for a decrease in the cost of wings, I'd only accept it if the duration was decreased to 1.5-2.5 seconds, making the skill more reactive than a passive hard counter (also remove reflection cap). If a MDK wants to cast wings every GCD then that's their play style.
Shimmering shield is overpowered ONLY because of how easily it can be sustained in conjunction with what it does. It does too much for it's opportunity cost. Remove the magicka on return and the skill would be [more] balanced. Shimmering shield could just as easily be compared to Harness magicka in this regard. Stam DKs cannot have 100% uptime on wings, yet stamens can achieve virtually 100% uptime. The issue isn't the effects of the skills but rather the uptime. 100% Negation of the bulk of your opponents offensive pressure is much more damaging than both 135% reflected projectiles and Major Heroism combined.
I agree on hardened armor, its a well balanced skill, personally prefer volatile armor to have better chance against cloak users, but still, I am tired of seeing desperate changes to magDk that doesn't solve their pve issues, while making them OP cheeseballs in pvp.
What stamDK really needs is actual damage passives, instead of the useless combustion and World in Ruin passives.
Both of those provide nothing useful to stamDK.