I'm definitely a believer in brakes on anything being towed over 1,500 lbs. Unlike others I prefer electric to surge brakes. They can be preset with the controller as to how and when the brakes apply. I have an equipment trailer with a 10,000 lb. capacity and a dolly. Both have electric brakes. I much prefer them to the surge style especially over rough roads and uneven ground. Over the years I've had several HD equipment trailers with surge brakes. I traded them all off in favor of ones with electric brakes.
To me they are far more trouble free than surge brakes over time and require similar maintenance. Both styles need the shoes adjusted from time to time if they are the drum configuration. The fluid needs to be changed on the hydraulics to avoid boiling or rust in the cylinders.
I agree electric brakes aren't the best choice on boat trailers. However for general highway and off road use I believe they are more than adequate with less hassles.