Salt & black pepper are gimmes. Garlic is a no-brainer. Worcestershire sauce (which has garlic, salt, onion, among many other things) is the perfect complement to beef, in my opinion. As far as herbs, thyme is synonymous with beef dishes and can be part of any dry rub for beef. Wanna make your brisket taste even beefier? Inject it with concentrated beef broth. Tastes great! What could go better with beef than more beef, right? As far as wood smoke goes, hickory & mesquite are great when grilling burgers, but they can easily become overpowering when used alone in a smoker. For low-and-slow smoking, I like to use pecan wood. It has a flavor that lends itself very well to beef without becoming too strong after a long period of time.