I like these old-school Kelsey 81741 controllers:
https://www.ebay.com/itm/Vintage-Ke...ontroller-w-Manual-And-Ford-Plug/222635749605
I've found them on basically every single old Ford I've bought.
They just plain /work/. Turn the knob on the side higher or lower depending on your load, and the inertial system does the rest.
In a panic situation, grab the manual lever and pinch it together and you'll lock the trailer brakes if you fully engage it.
I don't like the newer ones with buttons and adjustment that way, like my parents' newer Tekonsha Prodigy P2 controller. Biggest POS ever.
Edit:
I think I've seen a number of the Voyager controllers as well; same deal as the Kelsey one - squeeze the trigger and a single adjustment knob.