TL;DR
Problem: grim focus is lacking functionality
Solution: grim focus should grant major brutality/sorcery. Drain power would lose major brutality/sorcery.
Problem: mark target is lacking functionality.
Solution: mark target should grant minor vulnerability instead of major fracture/breach. Teleport strike would lose minor vulnerability.
Problem: lotus fan is overloaded with functionality.
Solution: teleport strike should lose minor vulnerability. Ambush morph should stun the enemy, even if they are a player.
Problem: incapacitating strike is lacking functionality, on account of minor mangle having very limited usefulness.
Solution: incapacitating strike should lose minor mangle, but stun at the base ability cost of 70 ultimate (instead of 120 ultimate)
Problem: veiled strike is granting too much defense and not enough offense for an offensive spammable.
Solution: veiled strike should be moved to the assassination skill tree, and blur should take its place in the shadow skill tree. Surprise attack should be given major fracture, concealed weapon should be given major breach
I understand why ZOS is rebalancing the NB class. I also agree with their stated goals in Update 22 Combat Direction. And, for the most part, they have been pretty good at working toward those goals in their most recent changes. But the class is nowhere near done, in my opinion. There are a few aspects of the class that still need work, and the following is my detailed explanation of why, followed by some potential solutions to how they could be resolved.
Goals of Class Rebalance, According to Update 22 Combat Direction
1. Eliminate redundancy in class toolkit. If one skill grants a certain function (ex/ major expedition), no other skill within the same class should also grant that function.
2. Redistribute skill functionality. Some skills have too much functionality, while others have too little. The goal is to try to balance functionality between individual skills.
The State of the NB Class as of v5.0.1
1. Redundancy has been resolved. With the removal of fracture from surprise attack, expedition from cripple and double take, and maim from mass hysteria, there are no more instances of multiple NB class skills granting the same function.
2. Functionality between class skills is still not balanced. Some issues of overloaded functionality have been resolved (ex/ surprise attack losing major fracture, incapacitating strike losing major defile, grim focus losing minor berserk and minor endurance), but others still exist (or in some cases have been introduced). Other skills have gained much needed functionality (double take receiving snare removal and immunity), but some others are still underwhelming. I will address these individual cases in detail, which brings me to:
Problem Areas within the NB Class as of v5.0.1
1.
Grim Focus and it's morphs is lacking functionality. With the removal of berserk and endurance, this skill is now the only skill in the game (accross all classes) that does not give anything back to the user upon the initial cast. 100% of the functionality of this skill is reliant on the user activating the ability (for resource cost), successfully landing 5 light attacks on an enemy, and then activating the ability again (for more resource cost). To gain the benefit of this skill, the user must sacrifice 2 GCD and also deplete their resources twice, all the while adhering to the skill's complex conditional of landing 5 successful light attacks.
No other skill in the game does this. Its an empty skill. Relative to the cost and functionality of other skills in the NB toolkit, this one is severely lacking.
2.
Mark Target and its morphs is still lacking functionality. To bump up the relative functionality of Mark Target, major fracture was removed from surprise attack, leaving Mark as the only armor debuff in the NB toolkit. This, however, does not increase the value of the skill on its own, especially when compared to similar skills like elemental drain. Both of these skills provide a major debuff to the enemy's armor, can be used at range, and have similar durations. Mark target costs resources though, where elemental drain does not. Mark target can be applied to only one target, while elemental drain can be applied to many. Mark target's additional functionality (a heal when the marked target dies) relies on a conditional, while elemental drain's magicka steal does not. For the added inconvenience Mark Target brings in comparison to elemental drain, it's benefit is extremely underwhelming.
3.
Lotus Fan (morph of Teleport Strike) is overloaded in functionality. This skill acts as a gap closer, applies minor vulnerability to the enemy, snares the enemy, and provides a very strong AoE DoT. Compare this to cripple, which is only a single target DoT and immobilize (half of what Lotus Fan is), and the imbalance in functionality becomes clear.
4.
Incapacitating Strike is lacking functionality. Right now, minor mangle is being applied after the damage portion of incapacitating strike. In PvP, this means that after using incap on an enemy, mangle is reducing their max hp by 10%, but this 10% of their hp has already been lost due to the damage of incap itself or the damage of other skills used before incap in combo. It is contributing nothing in PvP. In PvE, mangle can be useful for eliminating potentially millions of hp from enemy bosses. But this is only the case with 100% uptime, and this is not achievable given the ultimate cost and short duration of mangle provided by incapacitating strike. Minor mangle is adding virtually nothing to the skill, leaving the only difference between Incapacitating Strike and the base skill, Death Stroke, to be that for increased ultimate cost the ability stuns the enemy. Compare this to the other morph, soul harvest, which gains major defile and also ultimate generation for killing enemies and incap becomes extremely underwhelming. If you compare incap to dawn breaker (which costs only 5 ultimate more), the skill becomes even more underwhelming. Dawn breaker does everything incap does (for a similar cost), but acts as an AoE when incap is single target. The DoT of DB offsets the 20% damage increase of incap. Incapacitating Strike is definitely lacking, especially considering how it is an ultimate ability.
5.
Veiled Strike has enough functionality, but it's focus should shift away from defense and toward offense. As a spammable attack, this skill should be used primarily for its offensive capabilities. But as a skill in the shadow tree, it is currently granting the user defensive bonuses in major ward and resolve on account of the shadow barrier passive. With the boost to power extraction's tooltip damage and the removal of fracture from surprise attack, this single target spammable is just barely ahead of the NB AoE spammable in terms of damage output. I find myself primarily using this ability for access to major ward and resolve. This skill should be more oriented toward offense, and not defense.
Potential Solutions
1.
Grim Focus and it's morphs should grant major brutality/sorcery. Providing these major buffs would distribute much needed functionality to this skill, while at the same time keeping the overall power of the NB class unchanged because they already have access to these through other skills. To resolve potential redundancy issues, major brutality/sorcery should be removed from drain power and its morphs (which provide enough functionality on their own without these buffs).
2.
Mark Target and it's morphs should apply minor vulnerability instead of major fracture and breach. This would provide a very powerful debuff that is capable of stacking with outside sources of fracture and breach, and make the skill a lot more valuable in group play, while keeping almost exactly the same value in solo play. To resolve redundancy issues, minor vulnerability should be removed from Teleport Strike and it's morphs, which brings me to:
3.
Teleport Strike should no longer provide minor vulnerability, and the Ambush morph should stun the enemy (even if it is an enemy player). This change would remove some of the functionality from the currently overloaded Lotus Fan, while at the same time keeping the Ambush morph up to speed. The removal of minor vulnerability on this ability opens up the door for minor vulnerability on mark target as well.
4.
Incapacitating strike should lose minor mangle and instead stun the enemy at 70 ultimate (the base cost of the ability) instead of 120 ultimate. The loss of mangle wouldn't hurt the skill much (uselessness of mangle outlined above), but it would allow for the price of the stun to be dropped down to the base ability cost in compensation. This way, in comparison to the base skill death stroke, incapacitating strike would flat out gain a stun (without the conditional of a higher cost) which would allow it to compete with soul harvest's major defile and ultimate generation. It would also differentiate it from Dawn breaker, allowing it to be a cheaper, single target alternative.
5.
Veiled strike and it's morphs should be moved to the assassination skill tree, and blur and it's morphs should be moved to the shadow skill tree. Then, surprise attack could provide major fracture and concealed weapon could provide major breach. Having major fracture on surprise attack was too strong because, as a shadow skill, surprise attack was also granting the user major ward/resolve on account of the shadow barrier passive. Moving this skill out of the shadow tree would eliminate this defensive bonus, and allow the skill to keep its major armor debuff, emphasizing its offensive capability and highlighting the high risk/high reward playstyle of the NB class. Removing the major resistances from the main spammable attack would force NB to periodically go on the defensive as opposed to continuously attacking, emphasizing their bursty nature. I highly doubt this change has any chance of being implemented, but that's not going to stop me from posting it here as I feel it's the right direction to take the class.
The Effects of these Changes
In PvP, adopting these changes together wouldn't affect the overall power of the NB class, but it would make NB combat flow so much smoother. Right now, NB have too much of a "spin up time" on buffing themselves and debuffing enemy targets to gain maximum damage potential. They are expected to mark the target (for fracture/breach), then open with incap strike (for mangle), or with ambush (for vulnerability), or with drain power (for brutality/sorcery). Placing brutality/sorcery on Grim Focus instead of drain power and minor vulnerability on mark target instead of teleport strike both work toward streamlining the buffing/debuffing process and put less pressure on NB to open up a fight with a specific moveset. By condensing their buffs and debuff into two skills outside of their spammable (grim focus and mark target), it allows for a shorter time and resource investment to reach max damage potential and makes it easier to retain that potential while switching targets. It would also eliminate the opportunity cost of opening up with a specific skill instead of another. I believe these changes would drastically help the flow of NB combat, while both increasing balance between the abilities in the NB toolkit and also maintaining balance between NB and other classes.
On the PvE side of things, these changes would be a drastic boost to NB group utility. Letting mark target grant minor vulnerability would help open the door to NB in support roles (tank/healer). Right now, most healers are running infallible aether for reliable uptime on minor vulnerability. Putting a reliable source of minor vulnerability in the NB toolkit (without the drawback of gap closing to the target) would allow healers to forego infallible aether, and instead wear a different utility set. They still probably wouldn't be 100% meta, but it would definitely boost their competitiveness and finally give the NB class a near-exclusive class buff to bring to the table in group play.