I'd like to make this post in order to get an idea of what other people who play DRK think about the recent changes. Please try and keep it constructive criticism. Or at least mitigate the snark somewhat. Some snark is ok, but let's try not to jump it shall we?
First off, the good stuff
The Shadow Wall change is probably the single most noticeable thing. A 120s CD has been a long time coming. I would like to see something else to make it a bit more "DRK" than a simple Sentinel-cloned skill with 2/3 the CD. Maybe make it so that while active, self-healing and mana gain effects are doubled. This would give it some nice synergy with Sole Survivor and Souleater, as you could then time SS to expire during SW shortly after a buster and more or less self-heal the damage from it. It would be on a 2 minute CD, so not an amazing amount of self-healing, but something that rewards knowing a fight and planning ahead.
Speaking of Sole Survivor, now that it's a guaranteed heal upon expiration, I've found myself timing it in such a way as to help heal incoming damage from a number of mechanics. Guardian's initial tank buster in O7s is a great example, as you can pop SS shortly after you engage him as prep for his upcoming tank buster. I'd like to see a bit more control over SS, specifically in the form of a "detonate" button that expires the buff and provides the healing for it immediately. It's a nice challenge to try and time things with it's current duration, and maybe this suggestion is a bit too much, but I think this, coupled with the SW change above, would grant DRK's some much needed parity with PLD and WAR when it comes to clutch self-healing.
The Plunge and Dark Passenger changes are also quite welcome. I thought the 60s CD on DP would annoy more than it has, but it still tends to be up when I need it more often than not. The fact that it's also DPS neutral vs. using DA on almost everything takes off some of the bite of blowing MP on it vs. a single target, but it's still not something I use any more than I did before outside of AoE situations. The extra threat on it is quite nice, as is the extra threat on Plunge. DA+Plunge has annoyed me a few times, but it's not as bad as I anticipated. I actually like it as an opener now, as it completely removes the need for me to use Power Slash early on, and that's without a NIN in the group (but everyone else is using aggro management tools). It's great as threat maintenance throughout a fight as well.
Lastly, the Grit cost reduction and Darkside QoL changes are both just nice things to have. The Darkside thing should have happened awhile ago, but the Grit change was unexpected and very welcome. I also don't mind the Dark Mind change, although it feels a little boring without the DA option, even if it was something of a false choice. As a general rule, I like the idea of DA being something that "empowers" DRK in some way, as opposed to being considered a "baseline" for something DRK does. I like choice, and I'd like there to be choices, even if they're just relatively small ones, as long as they are impactful in some way. They can be niche, but they add depth to a class, and that depth is ultimately what makes a class worth playing imo.
Stuff I don't really feel strongly about one way or another
The potency increase on Power Slash is....nice. It's not a loss now, as long as you ignore the fact that you're using PS. I won't look a gift horse in the mouth, but I still maintain that tank aggro combos need something added to them to warrant their use beyond the initial pull. PLD RoH used to give a debuff that was powerful, and thus justified it's use every 20s or so, but now all three aggro combo's bring nothing unique to the table that a tank can't already get elsewhere. I've posted a number of suggestions that I would like to see implemented, but I have to go with one Kabooa (I think it was Kabooa) suggested once; add a "fractured" debuff effect to each aggro combo that lasts for 30s, stacks twice, and increases damage dealt to the target by 2% per stack. A single person could only apply one stack of the debuff, so in an 8-man both tanks would have justification for using their aggro combo at least once every 30s, since a 4% raid DPS increase is a small price to pay for using an aggro combo.
Alternatively, make aggro actually matter in this game. I'm happy that DPS and healer classes have tools that allow them to manage their aggro, but I miss the days of having to fight to keep aggro from my best DPS, even when they had Quelling Strikes up.
And finally, the bad stuff
Why can't I hold all these Dark Arts? I mean, if SE is going to give us more fights like Famfrit where we can sit inside the pot waterfall with Blood Price up and literally be swimming in MP while we're tickled for damage, then sure, the Dark Arts spam level is acceptable. But outside of that highly specific Grit-necessary circumstance, the level of DA is simply too damn high. I don't really know what to suggest here, as I'm not really sure what direction SE wants to take this. Don't get me wrong, I *like* Dark Arts as an idea. I like it in practice too, for the most part. It's just right now, there's too damn much of it. Toning it back a bit would be great, but I doubt that would impact DRK in a positive way overall. Something else would have to replace it, and either it would be a big buff to numbers (functional, if boring) or else some new mechanic to add on to an already mechanic-heavy class.
I wish I could add more to this one as far as suggestions go, but I'm really a loss.
Overall opinion
I'd call it a solid B. It's almost all positive, with the one glaring negative (to me anyway) being the increased DA usage on top of an already DA-hungry playstyle. My shining example of hope in this patch is the Sole Survivor change. It's a uniquely DRK mechanic that always grants a meaningful reward in such a way that it feels impactful to how the job plays. If the changes that are coming follow the SS change in terms of quality, then it's something I look forward too. Functional and unique beats out functional but boring any day of the week.