Caltraps seem to be regarded as a skill that I shouldn't use against anyone at hero.

Not sure if they might actually already do this but since it supposedly makes the person limp, it would be nice if they could make fleeing from battle a bit harder. Either that or potentially lag someone an additional round after they flee. If not that perhaps make it a bit more difficult for them move, basically a similar affect to being overburdened. It would be really cool if i could set caltraps in an area even if would be for very short as a way to lag someone running in briefly.

I see some really nice edges that seem to improve caltraps but in terms of malediction there always seems to be something better to do in a fight. Maybe I'm missing something?

For example, cal traps won't panic someone into fleeing. Then you disarm and if they have a full inventory they can't pick up their weapon, so you can grab that amazing weapon.

If you use a stronger move they'll just flee. Save the stronger one until they lag themselves out.

Also at low level you might as well use the caltrops.