I've had my 2003 5.4 Eddie since 2004 when it was 1 year used. I've tried a full set of slotted/dimpled rotors years ago. After about 20k miles, they would vibrate like a bad wheel bearing. I switched everything to the best pads and rotors I could get from Autozone and that set has been great for years.
As for the peeps saying "save the money for your next truck when this one dies", you do you. I love my truck, I know how it's been maintained and how reliable it's been. I just spent $2k at Ford to have them fix my AC. My parent's Lincoln service manager told them 8 years ago to tell me never sell it, or let him know when I want to sell it, because this year was built like a tank. He checks with them to make sure I still have it every time they go in. I have 168k miles on it and I plan to get to 250k, which aught to be another 8 years-ish.
I'd suggest putting your $2500 into AC (a requirement for me in FL), and a good set of name brand brakes. Maybe some new rubber lines and brake fluid flush will help with the spongy pedal feel. I'm considering this for mine for similar reasoning.