Initial impressions after a couple of games with the promo heroes/villains:
DW Fixer: He's one of the heaviest hitters now, at the cost of some of his buildup. Its pretty easy to hit multiple targets for 5-7 points, but you may have to skip turn if you really want a specific tool or style (or confer with teammates to find a sacrificial card). It really helps to have him go first. I found myself using tools that I normally kept in reserve (like the pipe wrench or tire iron) as one-shots. Multiple target tools (crowbars/jack handle) are still phenomenal, but I found myself holding onto them until someone else had a card for me to eat, or a salvage yard. Charge, while still good, was rarely played over a setup card or something for immediate consumption.
DW Nightmist: You absolutely can't rely on the amulet. It will drain her hand super fast, and she doesn't have an easy means to replenish. If you try to play her like normal nightmist, it feels VERY weak. If (instead) you shift focus to lesser-used relics like the book (to keep you supplied with spells), enlightenments, and use the amulet only as a last resort she's very fun to play. the cost is that she's more vulnerable. She feels less selfish, in some ways. Normal Nightmist can often be the last one standing, and drag on a fight forever due to mistform, the amulet, and having a large hand. DW nightmist has a harder time doing this (though she still can), but responds better to out of turn plays (since you know what you have coming up) and can coordinate better.
DW Expat: I've had some great games and some frustrating ones. Overall, I like the new power better. You'll have frustrating moments when you don't have the gun you want, or you don't GET a gun for a while, or your favorite one gets destroyed. But Aim allows you to setup even when you don't get a gun to start with, and makes the low-damage ones and hairtrigger reflexes more effective. I found myself using it every other turn (unless I got a shotgun). DW expat is an interesting example of a hero who gets FAR stronger with extra power usage. If she is the last one standing and other people can allow power uses you can get some truly silly damage going with shock rounds, unloads, and RPG's.
Promo Gloomy- He's really tough. things can go terribly wrong REALLY fast. If a zombie comes out at the wrong moment, it can heal him or the pouch. He hits hard. You can get swarmed with extra targets if things get destroyed. Its a rare situation where someone playing Unity needs to be at the absolute top of their game, since that many low-HP targets can equate to an army of cultists, zombies, pins, and relics. We had one game (in the realm of discord, with Unity) where Gloomy managed to play 10 cards during the hero/environment.
If you flip him, he starts doing massive AoE damage to everything. If you can weather the storm, redirect damage or shut him down for a breather you'll have a better chance. Or just throw everything at him and see who goes down first. I'd tentatively call him a high 3...but it could easily be a 4.
Promo Spite- Its difficult to get ahead of the drugs. Good Samaritans are a trap, since they give him an extra play, and with drugs out of the picture you're more likely to get something that destroys a victim or undoes your good work with a forced entry. He doesn't heal as much, so you can power him down. flip him and it becomes a brawl where he does more damage based on how many people are in the safehouse, though you have some ways of putting them at risk to help yourself. It really, really helps to have some means of lowering/controlling his damage.