Rant incoming, I've just recently upgraded the brakes on my red '97 C1500 so I can probably answer some of this.
The BEST thing you can possibly do to improve brake performance and pedal feel on these trucks IMO is to have the system bled (including the ABS module) using a Tech 2 or similar bi-directional scan tool. You will need a pretty large amount of fluid to do this. Once you've got all your new parts on I would be absolutely sure to get this done.
I would recommend installing braided stainless soft lines in place of the factory rubber ones. I used Russell part number 672340. This will also improve pedal feel quite a bit.
Regarding pads and shoes, look for something with a DOT friction code of FF or better if you want more stopping power. The two letter code lets you know the pad material's coefficient of friction, AKA how aggressive it is. First letter is cold, second letter is hot. Basically the higher the letter code, the faster they'll stop. GG will stop faster than FF for example. More info on that here on page 5:
https://www.gmt400.com/threads/ebc-yellowstuff-brake-pads-worth-it.47903/
Personally I used Raybestos EHT369H pads on the front (GG code) and Raybestos 675PG shoes on the rear (FF code). These are the most aggressive pads and shoes that I could find for a C1500 with the 10" rear brakes.
Rotors... I know there are a few different schools of thought on this but I went with Raybestos 56258PER slotted. I've read that slotted rotors help with cooling for aggressive pad compounds. Not sure how true that is, but I've been happy with them so far. Whatever you do I would stay away from anything drilled, as those seem to be more prone to cracking and durability issues from what I've read. A good solid rotor would probably be fine too.
Drums... I went with the cheapest I could find (Raybestos 2572R) and it was a massive headache. They were out of round on arrival and created a pretty nasty pedal pulsation. My mechanic inspected them and found that they were so far out of spec that it made more sense to just buy a different set rather than turn them. I had him get a set from his local parts connection (not sure what brand) and those were fine. Long story short, just have someone make sure they're nice and round before you put them on no matter what you go with.
Calipers... I went with PowerStop S4299 remans. Why? Well because they're powder coated red of course. (My truck is red)
No complaints, they went on fine and work great.
While I was doing this I also bought all new disc and drum hardware, and about a gallon of Wilwood DOT 3 brake fluid. (EDIT - Raybestos wheel cylinders, too.) After having my mechanic install everything and bleed the system until fresh fluid showed up at all four corners, the truck has the best brakes it's ever had by far. My dad drove it a few days ago for the first time since I had all that done, and he commented that it never stopped that well when he owned it. The results are pretty impressive.
