Going to lose Sergachev or Vasilevskiy as you won’t be able to afford them both

You're still 3 players short of a roster and you'll have no money to sign Vas of Sergachev

There's an expansion draft next summer for Seattle, which is Tyler Johnson's home town. The hope would be that Yzerman convinces him to waive his NTC and leaves him exposed, and Seattle takes him (which would make sense, as he would be by far their most talented forward available). Otherwise, other teams that need depth scoring should be willing to take him - he's a very capable #2 center with playoff experience who can also play wing. Then, they free $5,000,000, they get another $2,000,000 when Carle's buyout comes off, and if the cap goes up by about $2,000,000, they have almost $13.5 million for both of them. I think Vasilevskiy gets $6,500,000 and Sergachev gets $5,000,000 on a bridge deal. They would then look to dump Killorn, and they can give up mid-draft picks, or, if need be, Somppi (one of the best in the QMJHL who should definitely be able to play on the NHL level). That leaves them with $9.5 million for Cirelli, Stephens, Joseph, and Meloche. Cirelli gets $4,000,000, Meloche gets $3,000,000 (or is replaced with someone worth that amount), and Stephens and Joseph are each signed short-term for $1,200,000 to prove that they can be consistently good before they get raises. The next season, the salary cap goes up more because of added revenue from Seattle, and they have some breathing room for contract expiries.

According to the NHL rules, a roster is to have at least 20 players and no more than 23. So, we have 20. If anyone gets injured, they are put on LTIR and we get cap relief on and can call someone up from the minor league. I explained how to re-sign Vasilevskiy and Sergachev in my post above.

Yes, but can you tell me a team that actually had a 20 man roster last year??? It doesn't happen. And what happens if Vasilevsky has an amazing season next year? Maybe he's only worth 6.5... But what if he's worth 8? Even 9? You think Johnson will waive his full NTC to leave one of the best teams in the NHL? What happens if Seattle says, "we could take Johnson, but this is one of the most skilled teams in the league, theres a better player available". I like your train of thought, I really do, but it just seems too implausible for me, sorry.

I mean, you may be right. This plan depends on a lot of things going exactly right. A 20 man roster is theoretically doable, but far from ideal. Vasilevskiy's value could be higher than people think it is now after next season. If Seattle refuses to take Johnson (now that I look at it again, either Karlsson or Sergachev would have to be available, which doesn't bode well for the Lightning), even with prospects or picks offered in addition, and/or Johnson refuses to waive his NTC to go to his home town because he's on a Cup contending team, they're in huge trouble. But, if something doesn't work out for them, they can trade Karlsson. Several teams should be interested in Karlsson signed long-term for $10,000,000, and they could easily get a pretty big package of prospects and/or a slightly less talented replacement for him and still win the Cup without surprising anybody. Or, they can keep managing well pushed against the cap. If anyone can do it, it would be Yzerman. If Johnson doesn't seem interested in Seattle, don't re-sign Sergachev and/or Cirelli. If Vasilevskiy's worth too much, it would be because he improved from an already Vezina-caliber effort, and in that case they can afford to get rid of someone and contend for a Cup.

There's certainly a reason that no team has contended for a Cup for more than a few seasons. The only way you contend is if either everyone on your team takes a huge discount (which you shouldn't count on) or if you get lucky with your contracts and have people making less money than they're worth, in which case you only have until their contract expires and they demand more than you can afford. It's been 35 years since someone won three Cups in a row, and it's never happened in the salary cap era. The Blackhawks are the closest thing we've had to a dynasty, and they could only manage to contend for about six years (and that included multiple first round exits between each Cup win). Now, they're in cap hell and are questionable for the playoffs. If everything goes right, Yzerman can keep this going for quite a few years, but yes, something can easily go wrong and it can fall apart.

Didn't Miller just sign an extension? That would be pretty underhanded to trade him away right after that unless it was discussed prior.

This is two seasons away. The trades with Ottawa and New Jersey would have to be this offseason, but they could wait on the J.T. Miller trade until next offseason, since they would probably have enough cap room until then.