Tom, I do not see excessive break wear with towing but I have some methods that I use partially because of my light duty tow vehicle and partially because they are good habits for all vehicles.
The pair of 5200 lb rated dexter axles is equipped with large and effective brakes. I have a Tekonsha controller that I set to make sure that the trailer is doing its job to stop its weight. I shoot for braking effort real similar to a non towing truck. Trailer breaks are cheap and easy to replace but they need manual adjustment. Really, jack up the trailer wheels and spin them one at a time and be sure you hear the swish-swish -swish of properly adjusted drum breaks. Mine needed adjustmentr from the factory. You also need them to all be adjusted the same to ensure even braking. I also check the hub temperature when I arrive at my destination to be sure the brakes aren't doing too much and to be sure that no one wheel is hotter than the rest.
I tow in third, not OD, and on my truck I get very good compression braking. I also have my truck equipped with a vacuum gauge so I can see the engine sucking hard to slow me down.
Rear drums on my truck also need manual adjustment since the OEM GM drum brakes are notorious for ineffective manual adjusters. The first time I did it manually I got 37 clicks of the adjuster wheel before they gave me the swish. Much improved brake feel and stopping power. Still I am on the original reear shoes but the fronts have seen a few sets of pads and one rotor replacement. I don't turn rotors, if they've warped it was because of heat and making them thinner will make them all the more likely to warp.
Rear disk brakes are a nightmare. In the GM world the half tons went back to drums. People are seeing rapid wear and the inner drum pbrakes are prone to failure. My guess is that the rear discs doing only 25% of stopping aren't getting heated well enough or maybe the extra mud, gravel, and salt in the rear compared to the front is hard on them.
You say you're looking at trailers, well I am very happy with my PJ and they are a national brand.