http://amazingribs.com/recipes/rubs_pastes_marinades_and_brines/meatheads_memphis_dust.html is my go to rub for pork and chicken:
3/4 cup firmly packed dark brown sugar
3/4 cup white sugar
1/2 cup American paprika
1/4 cup garlic powder
2 tablespoons ground black pepper
2 tablespoons ground ginger powder
2 tablespoons onion powder
2 teaspoons rosemary powder
I was skeptical of the rosemary powder since I am not a fan of rosemary at all but it does work great in this rub.
If I want to do a South Carolina mustard style pork butt I go with this rub:
1 Tablespoon dry mustard
2 teaspoons sweet paprika
2 teaspoon freshly ground black pepper
1 teaspoon garlic powder
1 teaspoon onion powder
1/2 to 1 teaspoon cayenne pepper
Generally speaking I leave the salt out of my rubs. I prefer to salt the meat separately, preferably 24-36 hours before cooking and letting it dry brine in the fridge. And for the keto people it is also unsweetened. But if I use this I like spritzing the pork with apple juice throughout cooking to provide some of the sugar that helps create a nice bark on the outside of the pork.
If I am doing beef all I use is pretty much an equal amount of kosher salt and coarse ground black pepper. Gives the beef a central Texas flavor.