I like simple brine for my pork shoulder. Like apple cider and water with a touch of apple vinegar. 2 -1 on the apple cider/water and maybe a cup vinegar. I don't like to add salt many do. You can do a dry rub after the meat is out of the brine and patted dry. like smoked paprika, cumin, garlic.....whatever trips you.....The time all depends on the size of the meat. A 8 lb shoulder I'll soak for no less than 8 hrs...up to 12.....Guess you could do it 24, but watch it if you are using salt it could make the meat very salty.
Never done a brisket, but I would think it would be good that way as well......I would think a soak in some bourbon would be pretty good, or some spiced rum......