Thanks for your year by year progression of possible Leaf lineups. I guess a few things we are still in question (for all teams) will be the performance bonuses for all players. And for the Leafs the possible disposal of Marleau in his 3rd and last contract year. I'm sure Lou and Marleau kinda know what might happen by we certainly don't.
Plus how good will Gardiner be....if he continues to improved play, maybe he salary will be too high for the Leafs in his UFA year. And the biggest questions are who are the Leafs defensemen in 2019/20. Zaitsev And Reilly and then the Leafs and their fans are hoping that young guys are ELCs are going to be good NHLers. Besides the players you listed Neilson and Borgmann are candidates.

Agree with what you pointed out. I'm working on several assumptions:
-players on my projected rosters achieve max performance bonuses each year (worst case)
-Marleau remains on roster (worst case), odds are there is a "Lou retirement" plan or move like you say
-Gardiner is a top pair LD (or even 1.5) in 2019 and both parties want him to stay a Leaf, plus pickings elsewhere make him the best option. But alternatively, a RHD for similar $ could be plugged into lineup if Leafs don't sign Jake.
-Prospects I showed are not necessarily the ones that make it but I wanted a realistic projection of who/when might need re-signing as RFA's. I actually think Borgman could well make the lineup, it will be best of (Dermott, Rosen. Borgman, Neilsen). I'm personally more sanguine about Neilsen, he needs to improve a lot on his defensive side of things and skating to make NHL.
- Ozhiganov is signed from KHL, again a guess.

Bottom-line is that even after 2019-20 with Marleau gone, Leafs have to run a tight ship, no easy cap space anymore with prospects becoming RFA's like Liljegren. (His ELC might slide a year.)

Billius: I know some folks think, OH NO, the Leafs won't be able to get all their players. Yep that can happen. But I would rather be in a position of having too many good players and having too trade one or two. Even if you don't get true market value, it's a lot better alternative than having too few good players and then you're chasing overpaid UFAs. Either way the Leafs would spend to the cap. After all these years, sure looks the Leafs will be about to "pick their own team" in advance into going wildly into the UFA market every summer.