Ok, I had a few goes with this and have a bit of feedback. I played in EoR and made the mistake of starting on Insane difficulty. It's been a while since I've played EoR and I forgot how rough the start is on Insane. Started a run on Nightmare and had much more success.
So, one thing I mentioned on the Discord already is the stat spread. Using both melee and ranged weapons with no talent for requirement or dam mod conversion means you end up having your points spread really thin, or just ignore one stat/weapon for a while. Cunning ends up being the most important stat, as the bulk of your damage comes from black powder shenanagins. With that said, once things got rolling, the damage from detonating black powder gets really high really quick, to the extent that you're only using your weapon attacks to touch off the powder anyway. I'm thinking this damage may fall off a bit later on and the weapon attacks will become more relevant, but haven't gone far enough to say, yet. So all in all, the stat spread may not be as bad as I initially thought it would be, it just creates this weird kind of curve where you want Strength and Dex very early for your weapon and armor requirements, then you want lots of Cun for black powder and unlocking more tinkers, and I expect it will shift back to Strength and Dex after most of the higher level Cun reqs are met. It's probably fine, but it's different from a lot of other classes, so it feels a little weird at first.
I think the Black Powder mechanic is really well done and I get a real kick out of spreading and detonating the clouds. It starts off a bit dangerous (which feels thematic and right), but at that point your steam gun can take things down pretty quickly anyway (since the mastery talent uses normal talent requirements and you can pump it up very early). Once you get Powder Trance the danger is reduced considerably, and once the flat damage resistance talent comes online you end up ignoring nearly all of the (already drastically reduced) damage. Then you can detonate a cloud you're standing in and laugh as everything around you dies.
One thing I wish the class had some more of is mobility/knockback. Having a couple talents that cause knockback would be great for shoving mobs into your powder clouds, and a talent for jumping away from enemies would also be great, to move away from the explosions yourself (mostly this would be nice early on before you can mitigate most of the detonation damage, which I'll admit is a pretty small window). Having one or more knockback/disengage talents that could also touch off the powder would be really fantastic.
Personally, I would like to see the class move to Steam-only and eliminate Stamina costs from their talents, along with removing Combat Techniques, Combat Veteran and Conditioning. Combat Techniques (especially Blinding Speed) is really, really strong on a class that doesn't need to use lots of Stamina. Combat Veteran doesn't offer much, and Conditioning scales on a stat that is going to be your fourth stat (at best), on a class that's already spreading stats thin. Losing Rush would be a bit of a nuisance, but aside from that, I think these trees (and Stamina) can all go. On the other hand, I wouldn't be opposed to seeing a new class tree that offers a bit of mobility and utility to fill in a bit of what they lose from Combat Techniques, Veteran and Conditioning.
Another way to go, possibly, is to replace 1h melee with just daggers and shift the class entirely to Dex/Cun and give them Mobility in place of Conditioning. Disengage and Tumble would play really nicely with black cloud positioning, and the class could probably stand to have some more damage mitigation, which Trained Reactions is great for. In the case of replacing Conditioning with Mobility, I would keep the Stamina costs on attack talents, but still remove Combat Veteran and Combat Techniques. Mobility might be a bit too good if it's the only thing using Stamina.
It would be nice if the Black Powder (talent) did a little something extra on activation. Once you've invested a few points and the action speed is increased considerably it's not so bad, but early on it feels kind of weird that it's basically just a worse Blinding Powder that has slightly better range. Any kind of a mild debuff would be an improvement, and it doesn't have to be on all black powder all the time, it could be as simple as something like an accuracy debuff on enemies that are in the area of effect when you activate the talent, for example.
Sometimes Grog-soaked Blade does not set off black powder when activated, but it's been inconsistent and I haven't found a pattern to it yet. Maybe it's just as simple as the attack missing the target, but I'm not totally sure at this point.
That's all I've got so far. Just roasted Outpost Leader John with two black powder detonations and I'm about to head inland and see how things go there, but so far I'm having a lot of fun with the class. I'll let you know if I run into any issues (no errors or anything so far, aside from that weirdness with the talent icons I mentioned on Discord) or if I come up with some more feedback.
(Also, bonus points if you can work a Mechno-parrot into the class somehow
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