Group tactics (high-AC front-line, second-rank spears, casters and archers in back) make a huge difference.
Keeping an exit path open and a defensible bottleneck can be important - if you read the early chronicles of the Grim Fist, there was at least one (and maybe two, I didn’t check) situations where the PCs retreated to a doorway where they could restrict the foes able to attack simultaneously. And at least one situation where a character died holding off an enemy for “one more round” while the rest of the party fled.
A Familiar with 3xHealing proficiency, whose sole job is to run around keeping everyone alive, is a discovery my group made early on. It achieves several goals at once: healing within a round, good healing within a round (and I allow the cure effect to count as magical healing), and no loss of party firepower to the healing action.
War dogs. Seriously. Even if two of my players still mourn the one an ogre ate.
At low levels, there should be a lot of fleeing. Most of the low-level monsters can’t move as fast as the PCs! And keep the heavy stuff in a backpack that can be dropped quickly - the Grim Fist was rightly famous among sellers of adventuring goods for how often they had to buy a new pack and gear.
If a party member has a high Charisma, Diplomacy is the tool of the gods. Chlodomer sweet-talked the party out of a lot of serious pain, and I strongly suspect that his Cha+Dip combination is why so many members of the original party are still around.
