How difficult is it to add electric brakes to a camper that does not have them I towed many things for an amusement company and know the value of having the electric brakes even on a light load.
How effective the brakes will be, is entirely dependent on the weight of the trailer. A really light trailer, like "many" popups. Will just bounce, and slide with trailer brakes. Unless you dial them down until they are not working at all. Been there done that.
My self. IF the trailer is under 2500lb , and you are using something other than a minivan. I wouldn't worry about it. But if it makes you feel better, have them put on.