OF maybe? Fowler is fine, and Heyward will play, but their 3rd spot has been a revolving door Szczur/Almora/Contreras/Soler/Coghlan. It's been productive, but they'd probably like to consolidate that into one 3+ win player.
I guess a good controllable starter would be nice too. Hammel, Lackey, and Arrieta are all in their last seasons of control in 2017, and probably none of them will be back.
But yeah, these are luxuries, not necessities.