I'm sorry, but I have to completely disagree with that. Mijin Gakure is also only a single hit. Beyond that fact, almost every 2hr is situational or worthless. Mighty Strikes is amazing, I won't lie. Hundred Fists can put out some great damage as well. Spirit Surge is pretty weak honestly, I use it from time to time but it is nothing ground breaking. Blood Weapon is only useful in certain situations with the right setup and good support while using the right weapon and only on difficult enemies that haven't been made in the past three years since everything newer builds resistance to it quickly and most of the old enemies are a joke now anyway; in other words, limited use at best. Perfect Dodge is kind of a joke, I do use it if I'm in danger of dying, but that is the only use and you can still die with it up, or die 30s later. Familiar is also a very sketchy and situational 2hr. Mijin Gakure is only really a weakness removal; useful but limited. Meikyo Shisui is also one of the more useful 2hr. Azure Lore was changed to be better and I still think it is pretty awful. I've used Trance from time to time, it is a good life saver, but it is a support only 2hr on a job that makes a good DD. Wild Card is just random, hard to really give it much credit. Astral Flow is extremely situational as well, and not really much of a damage improvement over normal BP; Alexander is one of the better niche uses for it. I won't go much into mages as the focus seems to mostly be on comparing DD 2hr, though I know BLM and RDM can do decent damage with both of theirs if they can live.
So, in a nutshell for DD 2hr; WAR is amazing and by far the most broken 2hr in the game. MNK/SAM are both good. DNC/SMN are only really support. DRG/BLU both boost damage slightly. DRK/THF/NIN/BST/COR are all extremely situational.
Now if you consider that the only 2hr in the game that have ever been changed(that I recall) are DRG and BLU, you will notice neither is on par with the best DD 2hr. Both are useful to boost damage slightly, but they won't absolutely decimate anything like WAR does, nor will they drop 10k+ damage easy like SAM or MNK. So I truly think that is about the damage range any changes to EES would put it at.
Some of the idea's posed here earlier are just plain absurd. Any barrage-type change would just be overpowering. I even think the high Rapid Shot/Snapshot increases would be overpowering. I'm just incredibly curious how much damage you all normally do per shot if you think changes like this would not break the game for RNG; likewise why so many of you seem to think RNG is just an awful DD.