I think Rizzo should consider going after Iglesias and Feldman from the Reds to finish off this trade deadline. Iglesias would give us a cost controlled closerfor the next few seasons who could be flipped if we belly up in 2019 after Harper leaves as part of our own rebuild. Feldman wouldn't cost much, maybe adding a C level guy to the Iglesias deal, and would give us a decent 4th/5th starter if Roark doesn't rebound. Feldman was also good out of the BP for the Astros last postseason so would be a good option even if Roark starts pitching like he's capable of pitching.
Maybe something like Iglesias, Feldman for Robles, Kieboom, Watson, and Cole. I think that's roughly equivalent to what the Yankees got for Miller last season and would still leave us with Soto, Fedde, and Romero in our farm system.