Rotors aren't your pedal problem. Replace rotors if they are under the spec.. If had them turned at a reputable place they should have told you whether there was enough left to remove. Like Richard said today's rotors are pretty much disposable.
Get your brakes including the ABS, bled thoroughly. Make sure your rubber brakes lines aren't degraded.
Bleed your brake system properly!
If you want/need the max towing package buy something that already has it. While you can add the parts, you can't legally tow more than the vehicle was able to when it left the factory. The only time this is likely to come into play is if you were over the max designed capacity of the vehicle but under what it would be with max towing package and had an accident.
My Silverado is a 2018 crew cab with a 5.3 6spd transmission and 155,000 miles I haven’t any problem with lifters or transmission. I experienced the “ Open and close driver’s side window” message for a bad ground wire connection.