You are right- the Plek essentially takes care of leveling and most crowning in one step using grinding wheels (probably diamond) that have fret dome shaped into the wheel. I don't believe it can dress fret ends however. It looks like nut slots are done with two bits, so probably not the best tool for doing nuts (E, A D use one diameter bit to do all of them, G, B, E use another singular bit to do those). Maybe that's good enough however, although I associate too wide of a nut slot with sometimes odd noises up there.