1. Replace Plague Leech. Plague Leech, at first glance, looks like a pretty handy talent. Your diseases run out of time all the time, so casting Plague Leech really quickly to get a free death rune from diseases that are about expire anyway seems like good times and a safe bet, right?
The problem with this talent is that unlike its tier-mates, Roiling Blood and Unholy Blight, it is a very clear DPS increaser. Essentially, if you are a raiding death knight in a non-casual raiding guild, you'll probably be expected to master the art of using Plague Leech as close to every 25 seconds possible, in order to get that extra death rune and push your DPS up.
In theory, this doesn't seem like a bad thing. Extra DPS is good, right? There are a few reasons why that's not clear cut. First, since it's the only DPS increasing talent on its tier, it's going to become the clear "right" choice, something Blizzard wants to avoid. Second, we like to avoid nerfs when we can. Being nerfed on live servers isn't fun, so in that case, being middle-of-the-pack DPS is an advantage. Get those extra sources of DPS nerfed now, and we won't have to suffer through nerfs on live servers.
Finally, most of the death knights' complaints for this beta can be summed up it one word: complication. We already have one of the most complicated resource systems in game, as we have to constantly manage a feedback system between runic power and three separate types of runes. Mists of Pandaria is only going to complicate that further via things like Plague Leech, the introduction of skills that require death runes to use, and the possibility of needing presence weaving to reach maximum potential DPS. Removing Plague Leech nips at least one of those in the bud and keeps the class from becoming so arcane that newcomers and even returning old hands don't find it so complicated to play as to be unenjoyable.
2. Combine the DPS presences. At this point, even Ghostcrawler is starting to see the issues with presences. In order for all of our DPS specs to function well, we need both that 1-second global cooldown and a whole lot of runic power generation. Unfortunately, the Mists of Pandaria talent revamp has gutted our runic power generation, moving most of it to Frost Presence. This means DPS specs are stuck with the bad choice of either going to Frost Presences for the runic power they need, or going to Unholy Presence for the global cooldown they need and finding that neither really completely fills the prescription.
Now, Ghostcrawler has indicated that Blizzard is strongly considering making the 1-second DPS cooldown baseline to death knights or at least putting it on Frost Presence and finding some other way to buff Unholy Presence. Personally, I'm in favor of just combining Frost and Unholy Presence and leaving it at that. Adding frost's runic power generation to Unholy Presence is essentially returning the runic power regeneration we lost due to missing talents, which then leaves every DPS spec free to continue the high-speed rotation we're all used to from the Cataclysm era. It also leaves blood free to have the tradition 1.5-second GCD.
This may seem a drastic change, but since no one in the Cataclysm era uses Frost Presence anyway, chances are we'd hardly miss it. There's no real hard rule that says presences must be three in number, so just having a tank presence and a DPS presence seems like a simple, elegant solution.
3. Revamp the level 90 talents. The discussion of the level 90 talents has been relatively quiet, mostly because we've barely had access to level 90 long enough to testing, but the history behind them has been relatively interesting.
From an early point, it became obvious that balance the damage between Remorseless Winter, Gorefiend's Grasp, and Desecrated Ground would be tough. It was obvious that, all things being equal, PvE death knights would simply take what did the most damage. Certainly, that might sometimes be different depending on your spec, but for the most part, your choice would be pretty clear cut, and chances are that there would be complaining, if, say Dreadblade made Desecrated Ground incredibly powerful for unholy death knights, while Frozen Heart didn't do the same to Remorseless Winter. The developers decided to solve this issue by simply removing all damage from all three talents.
So there's a bit of discontent brewing that PvE death knights don't get a damage boost at level 90. The developers have indicated that they're OK with this, preferring that you make this choice about utility. It's worth noting it also neatly sidesteps the problems with damage. If a skill does no damage and costs no runes, it's a lot harder for it to unfairly favor one spec over another.
Of course, even if you ignore the fact that many other classes do in fact get PvE damage-increasing talents at level 90, it's not clear that there's much of a choice regardless. PvP death knights will probably take Desecrated Ground for the crowd control breaker, but as for PvE death knights, I fear they'll all take Remorseless Winter. With the ability to both slow and stun large amounts of mobs at once, it could all but trivialize trash farming, leading to some sort of nerf right off the bat and leaving PvE death knights with no real compelling or exciting choice at level 90.
Now mind you, I still like the idea of Remorseless Winter, and even without the damage, I am sort of excited to get it. But I also recognize that even without damage, the amount of control it gives you over a small area could easily be considered overpowered by Blizzard, in that one may see raid groups stacking death knights just so Remorseless Winter makes trash clearing (or even trash farming) trivial. Before that happens, I'd rather Blizzard take a look at the abilities again, reexamine them, and maybe consider some nice, solid rebalancing.
For my money, I'd love to see Gorefiend's Grasp become the new level 87 skill and its slot go to an optional direct damage spell with a CC component one could pick up for single-target fights. Desecrated Ground can remain the PvP option, and Remorseless Winter can cut down on the crowd control and be AoE damage instead.
Mind you, all of this won't fix every problem with the class. Runic Corruption, for example, is still woefully underpowered for DPS death knights but may be picked up by anyone who's even remotely casual, because Runic Empowerment and Blood Tap continue to be annoyingly complicated to use correctly. But for now, accepting that the beta could be over any day now, hopefully we can fit in a few last chances that'll make our class balanced and compelling to play and pray that we get some much-needed further adjustments as content patches roll out.
Learn the ropes of endgame play with WoW Insider's DK 101 guide. Make yourself invaluable to your raid group with Mind Freeze and other interrupts, gear up with pre-heroic DPS gear or pre-heroic tank gear, and plot your path to tier 11/valor point DPS gear.