Epoxy isn't a final finish regardless of how it looks, it's not UV resistant so it needs protected. That protection coating is the final finish that you want to look smooth. You'll be sanding the epoxy anyway, doesn't matter much if it's somewhat bumpy or not. The material just doesn't self level very well. Fast hardeners tend to get to initial gel too quickly for the epoxy to smooth out, but like I said, doesn't matter much.

Bill H.