The difficulty you describe coming to a stop is NOT normal even for the stock brakes. Many E-series weigh in heavier than you.
Are you downshifting on the long downgrade to keep the brakes cool? Use the engine for maintaining your speed, and the brakes only to scrub off more speed.
It sounds like your pads now are glazed from overheating. I think your best bang-for-the-buck is new pads all around, and a light rotor resurfacing. Maybe even turn them since you have pulsing, but I've found that a scotchbrite pad on a drill takes the glazing off the rotors just fine.
I recommend Napa Ultra Premium pads. They're a high-temperature semi-metallic pad. I've tried other much more expensive pads, and the Napas work the best.
Once the new pads are on, it's important you do a proper brake-bedding procedure. This won't just improve stopping power, it'll greatly improve rotor life as well.
https://brakeperformance.com/bedding-in-rotors.php
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