Did you know that a boat/trailer combination over 3000lb by Florida law requires brakes on every wheel? That's 4 hydraulic brakes if you have a 2 axle trailer. I never knew about this mainly because I never heard of it being enforced. Now I understand they nail people for this sort of thing regularly on the way to the keys.
I think one of the reasons there may not be a lot of focus on it is because boat trailer brakes go bad quickly because of the salt water, some people even disconnect them. I wasn't happy about the prospect of doing a lot of maintenance on brakes, so I researched the topic and discovered these Kodiak all stainless steel brakes. They're supposed to last a long time. Here's the best price I found Kodiak Trailer Slip On Disc Brake Kit ALL STAINLESS STEEL 5 Lug.