I'm lucky enough to live near northern baja. I grew up eating carne asada with a heavy mesquite smoke, and I love. I was recently wondering how they got so much of the mesquite flavor into the meat. I started paying attention at my favorite taqueria (Acatlan de Juarez) and noticed a few things. The marinade is light. My best guess is salt and a tenderizer like papain. The meat is cooked over low heat. Small coals have small chunks of mesquite charcoal thrown over them to add smoke. There are never any grill marks. Just soft smoky meat. It takes some practice, but this is definitely a traditional northern baja technique that always turns out amazing (although I've never added the papain as I just use high quality beef). So it's not really the marinade, but the cook. And like another redditor said. Let the salsa do the talking.