I love the new Byakko fight. Not just because it's fuggin' Byakko, but because, as a tank, I have a reason to use my aggro combo. The full aggro wipe that's done when he picks you up for the stack mechanic is a nice touch. All of a sudden DPS need to be cognizant of their aggro, and we tanks are incentivized to use our aggro combo's more than once in a fight. Hopefully SE will add more fights like this, where aggro management is actually a thing that needs to be addressed.
But maybe they won't. And that got me thinking that it would be nice, especially when I play on my DRK, if I had a reason to use my aggro combo outside of just aggro. WAR and PLD used to have a reason; BB combo was the highest DPS for WAR in the pre-gauge days, and RoH debuff was something you wanted to keep up full time on pretty much every fight, even if all it did was lower AA damage. DRK rarely used PS, but they had old Delirium to spice things up a bit. As of 4.0 however, there's no reason to use an aggro combo outside of the opener, and even that's not a sure thing if you have a NIN with you.
What I'd Like to See
WAR - this is simple. Add a trait, call it something like "Fractured" or "Bonebreaker" that adds a 10 potency DoT to Butcher's Block for 30s. Yes, this is basically Fracture tacked on to BB. No, the class will not be made too complex due to the addition of a DoT. If anything, it would be nice if you could make it synergize with IR in some way. Prepping a BB combo, hitting IR, finishing the BB combo, then moving into FC spam would certainly be more interesting than what we have now, while also not being overly complex. Potency numbers can be adjusted of course, since WAR is already top DPS, but I doubt an additional ~100 potency over ~30s is going too far.
DRK - DRK needs help. The core of the class is (some people may disagree with me here) pretty fun, but having a single combo that comprises more than 99% of your GCD's in a given fight....that gets old pretty fast. I propose two things for Power Slash; first, while in Grit, using PS combo will apply a debuff to the enemy called "Traumatized." While under the effect of this debuff, all damage dealt to the DRK and only the DRK by the debuff enemy is reduced by 3%. Furthermore, any damage taken by the DRK from that enemy increases blood gauge by 2 with a duration of 60s on the debuff. The practical effect of this is a slight increase in passive tanking power and greater blood gauge income while actively taking damage. Two gauge-per-instance-of-damage doesn't seem like it would be too much, even with a lot of simultaneous AoE flying around like in O5S. But even then it would create interesting moments where you get a burst of blood gauge gain. Naturally, this effect would stack with Blood Price.
Out of Grit, using Power Slash while under the effect of Blood Weapon would apply the buff "Closing In" for 30s, that decreases the MP and blood gauge cost of actions by 10, maybe 15%, and increases the maximum blood gauge by 50 for the duration of the buff. This is simply increasing throughput for the DRK. By lowering MP and blood costs you can crank out more DA's and Bloodspillers over the course of a fight. An extra 50 gauge to the cap means you could also throw out TBN for utility purposes (help MT soak a TB, shield a vuln'd teammate) and not worry about wasting blood. The reduced MP costs offset this as a loss, giving more actual value to TBN relative to what it was, and potentially granting 3-4 Bloodspillers in a single TA window if planned/timed correctly. Any blood in excess of 100 that the DRK possesses when the buff duration expires will convert to MP at a 15:1 ratio. So if the you have 130 blood when the duration ends, you'll get 45x10 or 450 MP back. This is mostly a QoL thing to help ease a transition back in to Grit if necessary, but also to prevent a "loss" of blood gained while Closing In is active. You're obviously better off spending the blood if you can, but if you can't for whatever reason, then it's not a total loss.
PLD - PLD already has a DoT to manage, and they're DPS seems to be in a pretty good spot, so I figured let's bring the RoH buff back but in another way. Something that emphasizes the PLD's ability to protect their teammates. To that end, using RoH on a target applies the "Halonic Fury" debuff for 20s. The next damaging attack made by any player besides the PLD will apply a buff to that player called "Halone's Grace" that creates a shield equal to 5% of that player's maximum health with a duration of 15s. This will also apply a debuff to that player, "Halone's Judgment" that lasts for 20s and prevents the player from acquiring Halone's Grace while debuffed.
The effect here is to take the burden off of the healers and protect your team a little bit. You're trading a good chunk of DPS and MP regen by opting to use RoH over RA, but the benefit is that each DPS, the OT, and very likely the healers will gain a bit of extra survivability. This isn't much of course, but combined with Reprisal or timely use of Succor/Shake it Off/Divine Veil it can have a noticeable affect. Plus I'm sure we've all seen those times when a DPS survived with less than 5% of their maximum health. How many more have died by that much?
For the PLD, attacking a target afflicted by Halonic Fury will heal the PLD for 10 potency per attack. This will probably be negligible as far as being MT goes, but as an OT in SwO, with the normal GCD rotation, auto-attacks, and the extra AA's from being in SwO, it should amount to a decent bit of healing. Enough for the PLD to self-sustain as OT without much input from the healers outside of the big raid-wide aoe's and other such mechanics.
Will all of this happen?
Oh by the Twelve no. It's highly improbable to say the least. But it's fun to brainstorm ideas and talk about them.