I don't think the Flyers or Leafs have any reason to move Couturier, Patrick or Marner, and Nylander's name is only coming up because of the Tavares signing. I think they' probably find other ways to resolve whatever cap issues they have. Even if they don't we're probably looking at something around Nylander and Dumba, which doesn't interest me personally. That idea is beginning to take on a distinct Dumba+ for RNH air.
I think what Fenton has done so far is to keep the roster as flexible as possible in the hopes of finding a post-UFA "hockey trade" with a team that hasn't been able to do what it wanted to do in free agency. It's possible that someone gets pushed out of Toronto, but it probably won't be anyone we want. Other teams that may have been eyeing Tavares and missed out might be better partners: San Jose, Tampa Bay, Boston, etc. The Hurricanes are probably still looking to make moves and maybe the Coyotes. The Ducks haven't done much, nor have the Devils and they just brought Fletcher on as a senior advisor. There's no telling what the Islanders are looking to do after losing Tavares. There are probably others.
But the bottom line is we've seen two major trades (Galchenyuk/Domi and Hamilton/Hanifin) and a relatively weak free agent crop so far this summer, so there's probably still some significant movement that will happen. It's really hard to tell what Fenton is going to extract from that situation, but my guess is that it won't be something that hasn't seen much or any discussion on these forums.
And if the market is bad we probably wait it out into the season. Fenton seems like a guy that's comfortable biding his time.