As for rubs, simpler is often better, especially for a good flavored meat as you have. Don't try to cover it up, just enhance the beef...black pepper, garlic, salt, and maybe some onion powder, which gives a hint of sweetness. Then you may want to add a bit of paprika (mostly for color) & chili powder, but that's about as far as I would go until you find what your taste buds like.
I would go with open grate smoking until an internal temp of 135-140* is reached...for rare to med/rare, then remove it to rest. I would at least rest it under a foil tent before slicing, just to reduce the rate of heat loss. I generally give a large cut a full wrap in foil, unless I put in into a pan and cover it to braze after the smoke, example: pork butt, picnic.
If you've never tried beef smoked, you'll be in for a huge treat!