The problem with keeping Toffoli, Backlund, Hanifin, Lindholm.. or any guy past this draft and into next season is really simple.
If the Flames run it back with these guys and are in playoff posistion at the deadline, they'll essentially lose them for nothing because you cant trade them to contenders when you're contending. This has been a glaring issue with the Calgary Franchise for decades. We hold onto players too long, run into seasons where we're going to likely make the playoffs, hang on to said players then bow out in the first round and lose them for nothing.
Simply cannot afford to do this again... so I fully expect it to happen.