Based on comments on my last post on sequels, I've added another goal to my next campaign.
If it's heavy on the story side, tie the violence into the story. And even if it's not heavy on the story side--if it's more in the vein of those exploration campaigns I've been considering--tie the violence into that.
Not just in the "you must win to advance" sense. Have something story-related, or exploration related, happening during the fight. People switching sides, learning new and exciting things about antagonists, the characters are trying to execute some plan they've made. So there's a tactical level and a roleplaying, what would my character do level going on at the same time.
For exploration campaigns--I've never run anything like this, so my examples can't be pulled from my experience, as those are above. But the things you fight, and where you fight them, would reveal things about the location--you run into an owlbear, and that means there are owlbears in the area. Or you run into an owlbear, and you've never run into an owlbear in the area before, and you have fairly good reason to think that there are no owlbears in the area, that tells you something strange is going on.