Will waxing make my hair grow back thicker/stronger/darker?
Absolutely not.
Waxing does not cause you to grow more hair follicles. In fact, if you become a regular waxer, you will notice that your hair will become quite sparse and not as coarse.
When hair is shaved, it is cut off at the thick part of the hair, which is why you can feel stubble the next day. A properly waxed hair is removed from the root, and when the hair starts to grow back it is a new hair, very fine at the tip, so no stubble.
The only things known to stimulate hair growth are hormones: natural or artificial.