If the Leafs stick it out another year, they'll have Tavares' $11 million to improve their defense, overall depth, and possibly goaltending. Although they really need a true 1D, preferable at RD, Walker would be a good UFA option for second pairing if he doesn't demand more than $6 million and 4 years. They have more than $18 million with 16 players signed.
Samsonov / Woll could work with a more structured D but Samsonov is a UFA. Then again, so is Marner
Exchange Domi for Frost (on their lineup; not Domi to the Flyers!), sign DeBrusk, and bring in a new coach.