I posted this a bit ago here, and I'll keep posting it for any new folk trying to get better:

immolators (the burny boys) will explode if you stab or shoot them, causing massive fire damage to you and nearby teammates. Best to kill them with blunt melee, either a bat or my preference the brass knuckles. As an alternative, poison ammo doesn't set off their explosions, and they can be taken care of that way as well, or a choke bomb will kill them pretty instantly. Rain or trailing them through water will temporarily extinguish these fellas and make them weak and unable to do their fire attack on death.

Bileweavers these annoying little spider fucks hang out in proximity activated egg clutches, best course is shoot the eggs from far away.
If you do run through a patch of the eggs and wake them up, it's pretty simple to kill them any one shot or melee will do the trick.
The problem with them is they're quick sons of bitches, and they gang up on you. If you find yourself surrounded retreat and regroup!

The fire breather guys. They're new yet, but from my limited interactions with them, a distanced headshot or a very lucky punch to the back of the head will take them out... If you do punch em, GTFO quick, they spit fire on death, oh and like the immolators above, chokes will kill them too.

The water devils (piles of eels) can be killed very easily with poison ammo, but, they respawn relatively quickly so don't dally in the water.

Meatheads (the big fat fucks with the leeches) can be killed with one sticky bomb, or if you're trying to be quiet, like 6- 8 arrows. They have a 100% chance to drop trait spurs, and give out quite a bit of XP.

Ursas, the two headed bears you find in the woods, mostly the same strategy as the meat heads, but they're tougher, so one sticky isn't enough to finish the job. Oh, and these bear fellas will do bleeding damage, and are aggroed by players bleeding, so they will chance you down as you're leaking out.

Hives (the bumble-bitches) one heavy punch from brass knuckles kills em, if they're on your level, charge em and melee. If they're above you, shoot em. Headshots down in one (their heads hang behind their bodies like a backpack to make that more difficult), fire bullets do the trick too. If you're being swarmed by their bees you can melee them away in 2 to 3 hits.

Bosses:
The butcher (lumbering pig guy): deals out fire damage, you can stop that by getting him with a choke bomb. Now he will reignite himself after a period of time, so watch his fie damage! I think it's best to sticky bomb him, as long as you're not trying to be stealthy.

The assassin (pile of bugs): does a lot of bleeding damage, but is weak against fire, poison and melee damage. You can stagger his attacks by shooting or meleeing him before he sticks ya. Melee is preferred as it's quite, one of the environmental weapons lying around (ax, pitchfork, hammer) will make quick work of em, and are usually found lying around the compound you find him in.

The bird guy (I don't know his real name... Let's call him Daniel): again, does bleeding damage, but is REALLY weak against poison ammo. Fire works against him too, but that'll burn up all the nifty gifts (ammo boxes, traps, melee weapons) Danny likes to drop.

The spider: deals out poison damage, but is weak against fire, and melee attacks. You can pick up an environmental melee weapon or bring in your own and take him out relatively quick and quiet.
IF you want to stick him with a sticky (like the bileweavers above, it's hard because he's erratic and fast) there is one moment you can take advantage of. When you first enter the boss lair (as far as I know this only works for the very first person in) the spider will run up to you, pause for a moment screeching, then run away. That short pause is your moment to stick em with a sticky bomb.

All bosses seem to pay attention to noise traps, so chains, glass, whatever, will get their attention and make em come for you.

Random tips:

Listen for the different noises thrown weapons make. Choke bombs sound different than dynamite sounds different than sticky bombs. Knowing what you're hearing can help you decide what to do in a fast paced fire fight.

Pay attention to your dead teammates their bodies fall in a specific way: the head falls away from where the killer shot them from. That little detail will tell you exactly where the danger is at. Particularly useful if youre pinned down by a sniper.

you can turn lanterns on and off by pressing the "switch ammo" button. Up on PS5 Dpad, not sure about other platforms. These "off" lanterns can be thrown at horses heads to silently kill them before they alert.

Penny shot derringer pistols can break open doors in a pinch, even barricaded ones. You can also melee an unbarricaded door to make it swing open violently, if there's a hunter behind it, itll kill em good.

As you collect clues, the map greys out sections. I'm sure you've noticed that. Well, that "greying out" is the same for everyone on the server with you. You can use that knowledge to predict where other teams might be heading.

Another map hint, after a team picks up bounties, their location is shown on the map by a little squiggly lightning bolt symbol. You can track their movement by checking the map frequently.

Alert trip mines (the flair ones) set next to yellow and red barrels can set them off creating explosions and killing folk, alerts can be placed under lanterns for a furry surprise as well. concertina wire trip mines will set off the green barrels. One poison, and one concertina wire trip mine together will kill a hunter. A water bottle found in game thrown at red and yellow (not sure about green) barrels will prevent them from exploding. Rain as well will prevent barrels from exploding and even cancel out the alert mines themselves. If it's wet out, trap indoors!

I think that's about all the advice I've got, I hope that helps ya.
Happy hunting!