The key is to know which enemies you can fight early and which enemies you should avoid.
What i do is make a 6/6 party. 6 ranged bros and 6 melee bros.
With this setup you can easily farm bandits, thugs and raiders. You farm thugs mostly to get lower grade weapons (with my setup you shouldnt be losing anything on thugs) and you will raiders in order to get medium to high grade weapons AND farm 110 armors and those -5 fatigue nasal helmets (they also drop 90 and 95 armors which you can put on archers).
What you dont fight before youre higher level are the undead (with exception of those… weidergangers? Zombies with strange German name, they are easy) and you definitely avoid goblins. I hate goblins so i avoid them pretty much always, but there are people who have specialized tactics for them i suppose.
Also fighting orcs may depend on your setup. If you have mostly melees, i would avoid fighting orcs until youre higher level (they will slaughter you), but if you have ranged brothers (specially if you have like 6 of them) you can attack even medium sized groups containing berserkers (which you can pick off 1 by 1 as they wear no armor usually). Its just when you run into orc warriors that problems start (they may require high level or very careful planning, those bastards are tough).