Here are a couple of options.
You offer Fowler a QO, in which he will rightfully decline. You then re-sign Austin Jackson and Coghlan to at least provide an insurance policy for the outfield.
You sign Heyward, and trade Soler and/or a package to net the young TOR pitcher which I think will be Salazar if they trade.
Cubs get 5 more years of Salazar, and Cleveland gets five more years of Soler. It is a good trade for both.
The Cubs greatly improve defense in RF, and get the TOR pitcher.
If that trade doesn't work, the Cubs might also be able to throw a package deal centered around Soler and some minor leaguers and go after either Tyson Ross or Cashner of San Diego, and Kimbrel. The Padres may want to relieve themselves of Kimbrels contract and start anew, and of course, besides Soler, the Cubs would have to kick in players like Villanueva, or Vogelbach, or Candelario, and some pitchers, and maybe they could eat half of Hammels contract and let him pitch in San Diego for 5 million per year.
This way, the Cubs still have a solid right fielder, a TOR, and now a closer to go along with Rondon, Grimm, and Ramirez at the back of the staff.
Then the Cubs can find a short term veteran pitcher such as Kazmir or Lackey. If they could get either one at 2 years and 15 million per, or 3 years and 35 million, it would be worth it IMO.
Two scenarios would be
Arrieta
Lester
Salazar
Lackey/Kazmir
Hendricks
or
Arrieta
Lester
Ross/Cashner
Lackey/Kazmir
Hendricks
Line-up
Jackson CF
Heyward RF
Bryant 3B
Rizzo 1B
Schwarber LF
Castro 2B
Montero C
pitcher
Russell SS
Bench Baez, Coghlan, Szczur, Ross, La Stella
Let Coghlan and Jackson switch out in CF for a year in the hopes that Almora becomes ready offensively, and hope that Jackson can return to his career average of .333 OBP.
Plenty of veterans and thump in the line-up. Good starting staff, good bullpen, good speed, and enough high OBP guys.
I know it's wishful thinking, but it stays within payroll range of not blowing it out of the water, even if they pick up pitcher like a Kazmir or a Lackey.
I would estimate payroll to be in the 155-160 range, knowing full well that 13 million comes off of the books the following year for the E-Jax debacle.