I honestly don't think this is written in stone but I think Kuznetsov is the big deciding factor. If he's a legit 1C then it helps tremendously. If he's not and they lean too heavily on Backstrom the team is in trouble. McMichael will probably initially slot in as 3LW before taking over for Eller and I think Kuznetsov, Backstrom, and McMichael is a really attractive 1-2-3C lineup, assuming McMichael continues on his current trajectory. Perhaps McMichael can bump Backstrom down to 3C and Backstrom can be more of the shutdown, matchup center instead of being relied on to provide a ton of offense.
Oshie will be gone after this season which opens up more cap space to find a younger and faster RW. Vrana and Wilson are still improving and are very good wingers that can skate and score and should be mainstays in the top six for a long time. McMichael looks like he's going to be the young injection of speed and offensive talent they really need in the middle six. Carlson, Orlov, Fehervary, and Alexeyev are a nice foundation for the defense (I see Alexeyev as an elite 3LD or a serviceable but not as good Orlov replacement) and Samsonov looks like the answer in net for the next decade (hopefully). Hopefully Protas and Leason are NHL guys too because they're both big and can score.
Certainly things have to go right in terms of player development and their big three of Ovechkin, Backstrom, and Carlson can't fall off a cliff but I don't think it's a guarantee that they're going to suck in a few years.