I have used just salt and pepper and it is just fine. My normal rub has a tiny amount of sugar in it, but, certainly not needed. I think just salt would not suit my taste, I like the bite of black pepper. But, nothing wrong with just salt.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"perhaps...but then again...maybe not..."