Step Two: Max Domi, Right Wing
Recent hot streak aside, the problem with Max Domi on the third line has already been demonstrated by Sheldon Keefe last year. Essentially, since he's so bad defensively you end up relying on the fourth line to play tough defensive minutes, which is self evidently stupid - if they were capable of playing tough minutes, they wouldn't be on the fourth line to start with.
This ends up screwing with the entire rotation and deployment of pretty much every line. An offense-only third line means less scrumptious offensive draws for your top players, because you've got almost no choice but to give them to the Domi line otherwise it will get blown out of the water.
For about 20% of a season, Max Domi scored like an Art Ross winner. He posted nearly 4 points per 60 on Matthews' wing, and it's bizarre that the Leafs have turned their back on this. By playing Domi with Matthews, the Leafs essentially get a free superstar upgrade to an otherwise bad, or at least, problematic-to-deploy, player.
Step Three: Yanni Gourde
I've written that the Leafs should aim higher than Yanni Gourde, and if they don't plan on moving one of their stars to the third line, then they certainly should do so.
Yanni Goude alone isn't going to provide the kind of depth scoring this team needs, nor is he alone going to vault them into the upper echelon of Cup Contenders. If the Leafs main upgrade turns out to be Gourde, it will be a failure. If he is their second best addition, I'm all for it.
Gourde should be a cheap, servicable upgrade, and as the second-best acquisition, he will fit quite nicely. The Kraken are closer to the Ducks than they are to the last playoff spot, so they're going to sell. Gourde is a pending UFA and the way to add him is with double-retention.
The Leafs can't afford a draft pick here, but Topi Niemela and another B-level prospect should be more than enough to tempt the Kraken and earn some salary retention. Maybe a couple mid-round picks can be used to get another team to retain some money as well.