I would judge Bottas to be equal to, or greater in pace, and certainly far better in the wet. In qualifying, Nico was good and only got better because he had to in order to beat Hamilton. In racecraft Bottas is a very clean driver, certainly not dirty and I don't believe Bottas to be the type of driver to park his car in Monaco to secure pole.
People can only rise to the occasion when given a chance. Let's see what Bottas does, but I haven't entirely bought into the line that Red Bull has "the" driver pairing of the grid.
When you are torn between choices, always pick the one that will make the best story. ¯\_(ツ)_/¯