With all the big combat balance changes out of the way, I wanted to take a moment to look at where combat skillsets are in terms of skill viability, by which I mean "are there valid and viable scenarios for using every skill in the skillset?" I'm a firm believer that if a skill is useless, it shouldn't even exist, and the goal of this is to try and find skills that are currently certifiably pointless to train. I will be using 2HA as my template for this, both because it is what I am most familiar with, and also because I believe is it in a near-perfect spot for this after the latest round of changes. I'm going to start with a brief overview of each of the moves (many of them will be lumped into one section because they share enough similarities to do so), and then call out -2- moves (HUGE improvement from pre-changes) that are currently classifiable as useless in practicality, and detail why they are currently and what simple changes could remedy that. Omitting blocks, falling strike, stepping slash, swinging disarm, and stat skills since their use and application are obvious.

Starting with the good stuff that needs no change and has a viable strategic use and is therefore worth investing SP in:

1. Easy Moves (chop, slash, swat, strike) - Beyond their base difficulty of easy, all of these have a very specific use, and a drawback that makes them not the end-all-be-all. Chop, swat, and strike are all easy to land by default, and slash is easy to land with specific opponent-based aiming; chop and slash are also either-range, providing some high accuracy moves for long range rotations. The damage on these moves is decent, but they have the downside of being generally about a second slower than the rest of the skillset. This means that they are useful against more defensive targets, but are not automatic must-use skills all the time.
2. Overhead Chop - An average move that is the top rotation-friendly move damage move in the skillset, only being outdone by stepping slash and low-roll-over-success ankle/arm hook attempts. It has the versatility of being either range, and is generally a great move. However, it has a lower to-hit bonus than most moves in the skillset, and combined with its average difficulty, means that you'll use it against opponents that don't completely outclass you defensively.
3. Cross Chop - The newly-minted darling of the skillset with the recent changes, this is a move you'll likely have in your rotation 95% of the time. Good damage, accurate, and usable at either range. It IS an average move, but even against defensive opponents, this is likely going to be in your rotation, only really taken out of the rotation in very fringe cases.
4. Woodcutter Slash - Good damage, but not very accurate and lacks the range versatility of basic slash and hip slash; also cannot proc Cunning Opportunist. HOWEVER, this is our shield-breaking move. So while you won't be using it in your normal damage rotations, when you need to break a shield, this is your option. A great example of a move that's not going to be universally used, but it worth training because the specific situations you would WANT to use it are commonplace enough for it to be completely justifiable.
5. Hip Slash - An average move with good damage and range versatility, but with the disadvantage of needing to take an aiming penalty to get around the most common defenses. This is a solid entry in most rotations, but you'll likely be leaving it out of rotations against particularly defensive targets.
6. Hook - Your weapon disarm. Still bad in PvE as with all entangling moves, but it's your go-to crowd control in PvP.
7. Ankle Hook - Your main pronemaker, but difficult to land on any opponent with reasonable defenses. As with all entangling moves, not good in PvE, but it has its place in PvP.
8. Haft Sap - Your most reliable crowd control move in PvE, but only because the bar is so low. This is a difficult move that will be hard to land on opponents with measurable defenses, but is a solid inclusion in close-quarters rotations against less skilled targets. It has good damage, hits the head (which is a good spot to hit!) and has a (low) chance to stun.
9. Up Slash - The most significantly improved skill in the recent changes, this difficult move has great accuracy bonuses and bypasses some of the easier defenses similar attacks would go up against using its default aim (mid-slash type move). It has good damage, but it has to follow-up a chopping attack, so its location within a rotation does have specific requirements. And despite its accuracy bonus, it is a difficult move, so against high-end opponents, there will be times you will be cutting it out of your rotations, but like cross chop, it's going to be in 95% of the time.

As you can see, 2HA has a wide range of moves that have enough use cases that you can absolutely justify investing in every single one of them, which is awesome. But, that said, there are still two moves that currently, you might as well leave at rank 1, if bothering to learn them at all. So let's get onto those:

1. Arm Hook - The ankle hook prerequisites were removed from this skill, but it is still an entirely bad skill to take; no one is going to bother investing in this skill in its current form. It is a difficult move that goes up against easy defenses, it's an entangling move so it's got its own PvE baggage, and it is a 100% worse option than ankle hook. Why is that? Well, ankle hook is also difficult, but it goes up against average or harder defenses in most cases instead of easy, so it will be easier to land pretty much 100% of the time. Additionally, if you DO manage to hook an opponent with arm hook and successfully pull off a swinging disarm, they are brought to a kneeling stance, rather than fully prone like ankle hook does. So even when you succeed with arm hook, it is worse than succeeding with ankle hook. So how do we fix this to make this skill viable? Easy: drop it to average difficulty. It's still going to be an uncommonly used move, but at average difficulty, it has enough of a difference compared to ankle hook that it will become justifiable to invest SP into both skills, rather than just ankle hook.
2. Backhand Strike - The redheaded step-cousin of Up Slash, this move did not receive any of the enhancements that up slash did which turned up slash from being a bad move to being a highly-valuable move. It is a difficult move that goes up against the same defenses as most of your other attacks (literally all of them except hip/basic/woodcutter slash), but doesn't do more damage and isn't faster with a minor unnoticeable exception (it appears to be fractions of a second faster when using a very specific type of axe, which is an otherwise inferior type of axe to use). It also must follow-up from a slashing type move, which are typically our more difficult moves to land in the first place. These factors, plus the fact that we aren't wanting for additional basic damage rotation moves, means that there is practically no reason to invest training in this skill currently. So how do we fix it? Simple: just give it the same accuracy/defense bypass bonuses that Up Slash received, but keep it short range only. It now becomes a move that won't see use in the most common rotations, but it will be a valuable enough addition to rotations against less defensive targets that you can justify investing in it for completely eliminating easy moves from your short range rotation against those opponents.

Overall, I've very pleased with the changes that came to 2HA. As you can see from the list, the weapon is in a near-perfect state as far as individual move viability goes (there's still a separate discussion to be had for legacy saps and entangles being significantly outclassed by their modern alternatives, but that's a completely different issue). When every move in a weapon is -practically- viable, meaning that the use cases for them over other moves is common enough that it's worth being able to do those moves well, things are great. You suddenly get a lot more excited about deciding what to train next, and playing with different rotations against different opponents, and that is a GOOD thing. it is the polar opposite of homework skills that are just "you must take this or you are bad" and remove the strategic decision-making to the progress of your character. So let's make everyone weapon skillset like that. Say "NO" to pointless moves (reminder: a move doesn't have to be "bad" to be pointless; it is pointless if there are no practical scenarios where you would choose to actually use the move over all your other options available).