I have a couple of crockpot roast beef recipes that are pleasers, too.
My most recent one is to put the roast in the crockpot, sprinkle a packet of Ranch dressing on it, put 1/2 cube (quarter lb) butter on that, put slices of 2 jalapeno peppers on top (seed the peppers and beware that you wash your hands before rubbing your eyes!). I start mine at night, usually, and it's ready for breakfast... hehe... or lunch.
Another one, if you like it hotter, is to put the roast in, cover with a can of beefy mushroom or beef broth, and top with a small can of chipotles in adobo sauce!
Yet another is to put the roast in, quarter an onion on top and then top the whole thing with a can of mushroom soup.