Nothing wrong with putting CF bits on your Raptor if you like it and don’t mind spending the money. I plan to replace the hood and fender vents with carbon fiber replacements. I think it will look awesome and I really don’t like plastic exterior parts. I’m not doing it for weight, I’m doing it because I love the look of CF. People can think it’s stupid all they want...it’s my truck.
My M3 is dripping in CF, both interior and exterior. Some functional (like the CF roof and diffuser) others aesthetic (like the mirror caps). I’m a CF *****. Love it.
I would say if you are prepared to spend really big money on big CF panels like the hood and fenders, then you will indeed get a performance benefit from reduced weight. However, if you are going to use your Raptor as a truck for hauling and off-roading, these very expensive parts are likely going to get pretty beat up, so I don't think I would do it. Like sombiekiller said, you'd be better off going with fiberglass, which gets you a weight advantage at a lower cost.
Ultimately, if I was trying to improve the performance of the truck, CF parts would be low on my list of things to spend money on. I would go for powerplant, suspension and wheel/tire updrades. Much more performance gain for your money there I think.