edit: Most up to date version of my post and comment on the Steam Discussion.

Just gonna mention that I'm using Windows 7 64bit because maybe other systems won't have these problems.

Resurrection build
The resurrection build is broken. Rez'd enemies don't deal or receive damage.
Eventually realized that the rez'd could be used as cannon fodder that refuse to drop. Guess that'd make you a Dark Souls Necromancer and your rez'd non-stopping skeletons.

Throwing Weapons build
Also broken. This is sad, btw, because there are new types of throwing knives now. :| Plasma Guns
Plasma's been working wonderfully, though. Having 2d and 2p in Plasma Guns along with 2d in Perception feels like overkill. 3H Harry almost died from a single headshot.

Repair
Repair started off working fine for me and, a session or two later, ended up bugged. Out of 5 tries, it failed to do anything (and wasted my repair kits) 4 times. Test this out for yourself before settling on your character's build. That all being said, the main thing I used it for was creating a Wrench Drone, so it was a worthwhile investment for me anyway, especially since Hacking lets me acquire the wondons needed to buy new items.
Tried it 3-4 more times on 2-3 items between 2 sessions. It ain't workin', y'all.

Others
Having 2p in 1-Handed Edge just for whatever knife I find has worked well so far. Don't wanna waste the Plasma shots on low-hp enemies.
Should clarify that I eventually spent a skill chip on 1-Handed Edge to get myself to a fairly needed 3p. 2p was manageable, but dem 3's be makin' a difference.
Hacking's been working fine. My Plasma Tech build's been working very well for me so far, but I admittedly haven't faced a second boss yet. The Wrench Drone supplements my absent Burglary skill excellently (generally speaking, highest skill in the party is the one that's used).

XP vs Exploration Mode Difficulty inb4 somebody tells me I'm wrong.

Burglary & Hack
Burglary and Hack uses the companion with the highest stat who's on-screen (or whichever is the closest to you?), so command them to stand somewhere off-screen when needed.

Companions
If you give them items, expect those items to disappear. If they say "This will be an upgrade", assume they're using those items. If you want to control which items they use, put them in the corresponding group (e.g.: melee vs ranged) and hover over their group icon to see which weapon's their current favorite (because that's the one they're using). Everything they have will be loot upon their death (yes, I've tested this... with explosive plasma rounds).

Discord
As always, gonna recommend the Discord in general for information and answers. Pretty much everything here is my own advice based on my own experience. There's plenty more to be found in the #mechajammer and #character-sheets channel.

This comment and the ones around it are hella helpful for figuring out your build, btw. Highly recommended.

Additionals:

Durability
If you somehow have a 0% durability armor in your inventory (because it didn't break for some reason), it's probably not factoring into your stats. On the flip side, my acidic knife has been stuck at 77% for multiple sessions now. :D

The infi-durability bug/blessing doesn't apply to everything. Upgraded a Machete with acid and hallucinogen then noticed the new main actually being affected for hitting crates and doors. I'm assuming the same will apply to hitting enemies. Hopefully, the acidic knife is still infi-durable.

I'm really unsure of whether or not durability affects companions. Still waiting for Aldo's club to break, but he seems to still be using it.
I thought it did for a sec, but seems to have been a bug considering his favorite switched back from Wrench after I put him in a Ranged group for a short while.

Not sure why companions stop autohealing from time to time, but it seems to kick back in without a problem during combat, so I don't mind it much.
My Wrench Drone, on the other hand? Tends to autoheal up to a certain %.

Drones
Save before you attempt to create a Drone. And make sure your companions are off-screen somewhere. The no-roll bug kicks in just like with hacking and burglary.
Like rez'd companions, Gun Drones do no damage. But-ah, they can whip (and nae nae)
Like rez'd companions, Gun Drones do no damage. :|

Underground
When underground, be vigilant about merchants and armorers who don't have icons above their head. Most will be under tents and turn invisible as you pass them by.

- No interface to transfer just part of an ammo stack - your guess is as good as mine as to what amount gets transferred and what you're left with. A simple pop-up and a "+" & "-" sign to control this, Fallout style - would have been nice here
-The incendiary laser ammo & plasma drip charges cause self-harm (this looks intended, actually)
- Can't attach more than one mod to a weapon - why have weapons with 2 mod slots, then?
- Autohealing and companions self-healing mechanics and using medkit decisions in general (when they do it and above what thresholds) is a complete mystery to me and it seems sooo random.
- Having equipped an excellent quality weapon with lotsa pips e.g. +7 or +9 etc, you just insta-stomp on enemies when you run them over with the car and you rarely just knock them out. Mmm, nice erm... "feature"? Much Carmageddon.
- I just made contact with a new gang (Hive), talked with the boss, all good, exited their base, then reloaded a few minutes later - they now have the status suddenly set as Hostile on the map now and turn instantly aggro whenever I step back into their compound. What gives?
- The angry rioters spawning and various gang mobs spawning right next to you are tiresome and happen too often. I just want to sit quietly for a moment and take in the music and the city atmosphere, may I please just have a moment?
- Whenever the above-mentioned rioters spawn, somehow my party instantly scatters in a matter of seconds. They just leave for good and they don't appear in the party menu anymore either.
- The ammo stacks duplication / disappearing act is seriously Fubar, people. I found out the best way to protect it in my inventory is to never exceed one full stack (I distribute parts of a stack to my party members whenever I get close to 90 units in a stack.)
- The shadow system is nice but unreliable. Randomly after reloading, you might be fully hidden in shadows even if you are directly in the light.
- Aldo (not sure about other companions skilled with impact) randomly switches between his favorite wrench and the excellent spiked club I passed to him. I later found out (when he died and dropped his items lol) that his wrench had a weapon mod attached, but otherwise the wrench was completely common. Maybe that's why he was favoring it?
- Raddo (not sure about other companions skilled with range weapons) randomly switches between the plasma and the slug pistol. I think he ran out of ammo, so I started heavily supplying him with ammo & he kinda stopped doing it. You know, again, a Fallout 2 type of interface, where you see the companions' inventory and you give them simple instructions like "use best weapon / armor" would have been enough here, instead of this entire guesswork.
- Created a drone from a pistol, but it can't shoot it (just use it as a melee which defeats the purpose...)
- Resurrection build is broken, effectively. Them resurrects do not attack and can't receive damage either...
- Thrown knives just fly off into infinity most of the time when they miss the target. There's little chance in getting back them expensive new types of throwing knives, which makes this build pretty broken as well. And the new items added - purposeless.
- Repair & hacking works, but just keep your party off screen so that they don't try to use their skills instead (this breaks both types of attempts as you basically do not roll the dice). In any case, at least for Repair, I had to invest heavily (2+ dice and some pips) to be able to repair my high grade weapons and armour. Did not try investing heavily in Learning first, though (I heard I basically get free Repair & Hacking skills as an effect)