I mostly just dry brine now and then add spices after a light coating of oil before cooking. I was big on marinading for years until I started reading Amazing Ribs. They do a lot of experiments that debunk common myths in cooking meat and specifically BBQing. Their
article on marinating was enlightening for me. The tl;dr is that marinades don't really penetrate meat very far, so short marinades are just as good as long marinades. Just get flavor on the meat. In fact marinades with high acid can be detrimental because of how they alter meat. Ceviche is "cooked" by citric acid alone after all. Brines, or marinades heavy in salt, with help break down protein to make meat more tender and enhance flavor. It also penetrates much farther than marinades, so it's the exception in that longer does do more. It's especially useful for thin cuts of tougher meat like flank steak. Oils don't do much for a marinade other than act as a medium for the spices and add a bit of flavor. Scoring the meat will allow marinade to penetrate deeper and provides more surface area for flavor to collect.
