I would be surprised if Ellis > Reilly, but I don't watch the Leafs enough to have any real opinion on how Reilly compares. But isn't it a moot point? Because don't the Leafs just want a top-pair RD, which Ellis would be for them. Whether he's a little better, a little worse, or about the same as Reilly wouldn't really matter.
But speaking of moot points, I do not believe the Predators will trade Ellis this year anyway, not for the OP offer or any other one that actually comes forward and makes even a little sense on paper. He's an important part of the Preds for 2018-19, at a magnificent cap hit. The Preds lean heavily on their Top-4 D, and they haven't signed anybody to take the load off that arrangement for the coming season, so Ellis is still a big part of the coming season for the Preds. Summer 2019 is a different story... come and ask us about Ellis then and depending on his contract and how well he played and all that, he might become available next summer, who knows. But he's not available now.