Make an offer to Span; also offer enough to sign either Heyward or Cespedes. If Span signs, he plays CF and leads off. Turner can bat second. He should be there now, and I don't understand Rizzo's logic. Maybe that Span will return on Friday playing as well as he did earlier this year...no ramp-up? If Span signs plus a big guy, then Werth honorably takes a seat. If Span walks, go all out for new CF.
Another outfielder? Ichiro. Make Taylor watch Ichiro hit. Over and over. Forget the home runs. The Nats need someone who hits like Ty Cobb, Sam Rice, Denard Span, or Billy Burns. Turner is probably one. Ichiro would be the 4th OF.
Take a look at the 1924 and 1925 Nationals, at the core players: Rice, Bucky Harris, Goslin, Joe Judge. Nobody hit many home runs -- nobody on any team hit many home runs at Griffith Stadium. Those guys each had an OPS of about .825 - .850 - .937. (Note: Rice and Goslin each had triples in the double digits, probably because the old stadium had a bigger outfield than current ballparks).
If pitchers have an advantage, for whatever reason, maybe it's time to hit like "dead ball" era ball-players? Or at least to have a balance...a couple of home run hitters and several guys who "get wood on the ball" and can run. Steal bases. Play hit&run.
For whatever new tricks appear in baseball, someone probably had a counter-move 75 or 100 years ago.