This is how I'd do it. Just 3 simple trades.
Gaudreau - Monahan - Silfverberg *
Tkachuk - Bennett - Perry *
Buchnevich** - Jankowski - Ferland
Versteeg - Dube - Hathaway
Giordano - Hamilton
Skeji** - Hamonic
Kulak - Stone
Lundquivst ***
Gilles/Rittich
Spoiler!
Flames trade to Buffalo:
- Smith
- Gilles/Rittich/Parsons (Pick one)
-2018 3rd pick
Sabres then trade to New York:
-Gilles, Rittich, or Parsons
-Lehner
-2018 3rd pick (Cgy or Buf)
Rangers trade to Calgary:
Lundquivst
My thinking behind this is if Buffalo wants to be a competitive team next year, and the Rangers are committing to a fill rebuild Lunquivst wants to chase a cup maybe.
Flames
In: Lundquivst
Out: Gilles, Rittich or Parsons, 3rd(2018 74 overall pick)+ M. Smith
Buffalo
In: M. Smith, 3rd(2018 74 overall pick)
Out: Gilles, Rittich, or Parsons, 3rd( 2018 63 overall pick)+ Lehner
NYR
In: Gilles, Rittich, or Parsons, 3rd( 2018 63 overall pick)+ Lehner
Out: Lundquivst
Flames trade the most get the best.
Sabres trade to upgrade Lehner to Smith.
Rangers trade for the future.