Mostly variety… For example;
-Wild enemies that just wander through the map, only attacking if they get too close to your Hearthlings. It feels more organic than rolling the dice on what new enemy will run directly at your town. You can attack them on purpose, or you can accidentally bump into them with a Trapper/Herbalist/any hearthling who’s out running around to grab something.
-Variant on above; enemies that wander around and compete for your resources. Wolves chasing rabbits, for example, or large prey animals grazing on berries or flowers.
-Animals with dens. More of a “Come get me!” option like the Zombies with their treasure chests or the Necromancer temples currently. Risk/reward of attacking them for bounty vs. being injured at the wrong time when “wave” enemies attack.
-More mischievous enemies that act like Goblins - Vultures or Wolves that steal your meat, for example, making Trappers a little more challenging to use.
-Enemies fleeing under certain conditions - severe injury, or refusing to come too close to fire if it’s nighttime, or flying away if they’re outnumbered.
-Wandering enemies that you might want to chase down - for example, deer or other “prey” animals that run away from you when chased, and aren’t reasonably attainable until you have archers or traps.
-Enemies that affect your hearthlings - applying unique debuffs, such as diseases, curses, or fear effects.
-Enemies that only appear when you’ve done something specific or have a specific resource - like variants of Stone Golems that correspond to a type of ore that you’ve been strip-mining beyond any reasonable need. Or, as above, enemies that compete for your resources organically being drawn to your town because you’ve consolidated them, like with the berry bushes.
Basically, I’d just like there to be more random enemy behaviors that can lead to interesting events. The best we get now is when Goblins or Golems or Zombies cross paths and fight.